[RFCs/IDs] [Plain Text] [From draft-ietf-html-spec]
Obsoleted by: 2854 HISTORIC

    Network Working Group                                    T. Berners-Lee
    Request for Comments: 1866                                      MIT/W3C
    Category: Standards Track                                   D. Connolly
                                                              November 1995

                        Hypertext Markup Language - 2.0

    Status of this Memo

       This document specifies an Internet standards track protocol for the
       Internet community, and requests discussion and suggestions for
       improvements.  Please refer to the current edition of the "Internet
       Official Protocol Standards" (STD 1) for the standardization state
       and status of this protocol.  Distribution of this memo is unlimited.

    Abstract

       The Hypertext Markup Language (HTML) is a simple markup language used
       to create hypertext documents that are platform independent. HTML
       documents are SGML documents with generic semantics that are
       appropriate for representing information from a wide range of
       domains. HTML markup can represent hypertext news, mail,
       documentation, and hypermedia; menus of options; database query
       results; simple structured documents with in-lined graphics; and
       hypertext views of existing bodies of information.

       HTML has been in use by the World Wide Web (WWW) global information
       initiative since 1990. This specification roughly corresponds to the
       capabilities of HTML in common use prior to June 1994. HTML is an
       application of ISO Standard 8879:1986 Information Processing Text and
       Office Systems; Standard Generalized Markup Language (SGML).

       The "text/html" Internet Media Type (RFC 1590) and MIME Content Type
       (RFC 1521) is defined by this specification.

    Table of Contents

        1.     Introduction ........................................... 2
        1.1    Scope .................................................. 3
        1.2    Conformance ............................................ 3
        2.     Terms .................................................. 6
        3.     HTML as an Application of SGML .........................10
        3.1    SGML Documents .........................................10
        3.2    HTML Lexical Syntax ................................... 12
        3.3    HTML Public Text Identifiers .......................... 17
        3.4    Example HTML Document ................................. 17
        4.     HTML as an Internet Media Type ........................ 18

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        4.1    text/html media type .................................. 18
        4.2    HTML Document Representation .......................... 19
        5.     Document Structure .................................... 20
        5.1    Document Element: HTML ................................ 21
        5.2    Head: HEAD ............................................ 21
        5.3    Body: BODY ............................................ 24
        5.4    Headings: H1 ... H6 ................................... 24
        5.5    Block Structuring Elements ............................ 25
        5.6    List Elements ......................................... 28
        5.7    Phrase Markup ......................................... 30
        5.8    Line Break: BR ........................................ 34
        5.9    Horizontal Rule: HR ................................... 34
        5.10   Image: IMG ............................................ 34
        6.     Characters, Words, and Paragraphs ..................... 35
        6.1    The HTML Document Character Set ....................... 36
        7.     Hyperlinks ............................................ 36
        7.1    Accessing Resources ................................... 37
        7.2    Activation of Hyperlinks .............................. 38
        7.3    Simultaneous Presentation of Image Resources .......... 38
        7.4    Fragment Identifiers .................................. 38
        7.5    Queries and Indexes ................................... 39
        7.6    Image Maps ............................................ 39
        8.     Forms ................................................. 40
        8.1    Form Elements ......................................... 40
        8.2    Form Submission ....................................... 45
        9.     HTML Public Text ...................................... 49
        9.1    HTML DTD .............................................. 49
        9.2    Strict HTML DTD ....................................... 61
        9.3    Level 1 HTML DTD ...................................... 62
        9.4    Strict Level 1 HTML DTD ............................... 63
        9.5    SGML Declaration for HTML ............................. 64
        9.6    Sample SGML Open Entity Catalog for HTML .............. 65
        9.7    Character Entity Sets ................................. 66
        10.    Security Considerations ............................... 69
        11.    References ............................................ 69
        12.    Acknowledgments ....................................... 71
        12.1   Authors' Addresses .................................... 71
        13.    The HTML Coded Character Set .......................... 72
        14.    Proposed Entities ..................................... 75

    1. Introduction

       The HyperText Markup Language (HTML) is a simple data format used to
       create hypertext documents that are portable from one platform to
       another. HTML documents are SGML documents with generic semantics
       that are appropriate for representing information from a wide range
       of domains.

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       As HTML is an application of SGML, this specification assumes a
       working knowledge of [SGML].

    1.1. Scope

       HTML has been in use by the World-Wide Web (WWW) global information
       initiative since 1990. Previously, informal documentation on HTML has
       been available from a number of sources on the Internet. This
       specification brings together, clarifies, and formalizes a set of
       features that roughly corresponds to the capabilities of HTML in
       common use prior to June 1994. A number of new features to HTML are
       being proposed and experimented in the Internet community.

       This document thus defines a HTML 2.0 (to distinguish it from the
       previous informal specifications). Future (generally upwardly
       compatible) versions of HTML with new features will be released with
       higher version numbers.

       HTML is an application of ISO Standard 8879:1986, "Information
       Processing Text and Office Systems; Standard Generalized Markup
       Language" (SGML). The HTML Document Type Definition (DTD) is a formal
       definition of the HTML syntax in terms of SGML.

       This specification also defines HTML as an Internet Media
       Type[IMEDIA] and MIME Content Type[MIME] called `text/html'. As such,
       it defines the semantics of the HTML syntax and how that syntax
       should be interpreted by user agents.

    1.2. Conformance

       This specification governs the syntax of HTML documents and aspects
       of the behavior of HTML user agents.

    1.2.1. Documents

       A document is a conforming HTML document if:

            * It is a conforming SGML document, and it conforms to the
            HTML DTD (see 9.1, "HTML DTD").

                NOTE - There are a number of syntactic idioms that
                are not supported or are supported inconsistently in
                some historical user agent implementations. These
                idioms are identified in notes like this throughout
                this specification.

            * It conforms to the application conventions in this
            specification. For example, the value of the HREF attribute

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            of the <A> element must conform to the URI syntax.

            * Its document character set includes [ISO-8859-1] and
            agrees with [ISO-10646]; that is, each code position listed
            in 13, "The HTML Coded Character Set" is included, and each
            code position in the document character set is mapped to the
            same character as [ISO-10646] designates for that code
            position.

                NOTE - The document character set is somewhat
                independent of the character encoding scheme used to
                represent a document. For example, the `ISO-2022-JP'
                character encoding scheme can be used for HTML
                documents, since its repertoire is a subset of the
                [ISO-10646] repertoire. The critical distinction is
                that numeric character references agree with
                [ISO-10646] regardless of how the document is
                encoded.

    1.2.2. Feature Test Entities

       The HTML DTD defines a standard HTML document type and several
       variations, by way of feature test entities. Feature test entities
       are declarations in the HTML DTD that control the inclusion or
       exclusion of portions of the DTD.

        HTML.Recommended
                Certain features of the language are necessary for
                compatibility with widespread usage, but they may
                compromise the structural integrity of a document. This
                feature test entity selects a more prescriptive document
                type definition that eliminates those features. It is
                set to `IGNORE' by default.

                For example, in order to preserve the structure of a
                document, an editing user agent may translate HTML
                documents to the recommended subset, or it may require
                that the documents be in the recommended subset for
                import.

        HTML.Deprecated
                Certain features of the language are necessary for
                compatibility with earlier versions of the
                specification, but they tend to be used and implemented
                inconsistently, and their use is deprecated. This
                feature test entity enables a document type definition
                that allows these features. It is set to `INCLUDE' by
                default.

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                Documents generated by translation software or editing
                software should not contain deprecated idioms.

    1.2.3. User Agents

       An HTML user agent conforms to this specification if:

            * It parses the characters of an HTML document into data
            characters and markup according to [SGML].

                NOTE - In the interest of robustness and
                extensibility, there are a number of widely deployed
                conventions for handling non-conforming documents.
                See 4.2.1, "Undeclared Markup Error Handling" for
                details.

            * It supports the `ISO-8859-1' character encoding scheme and
            processes each character in the ISO Latin Alphabet No. 1 as
            specified in 6.1, "The HTML Document Character Set".

                NOTE - To support non-western writing systems, HTML
                user agents are encouraged to support
                `ISO-10646-UCS-2' or similar character encoding
                schemes and as much of the character repertoire of
                [ISO-10646] as is practical.

            * It behaves identically for documents whose parsed token
            sequences are identical.

            For example, comments and the whitespace in tags disappear
            during tokenization, and hence they do not influence the
            behavior of conforming user agents.

            * It allows the user to traverse (or at least attempt to
            traverse, resources permitting) all hyperlinks from <A>
            elements in an HTML document.

       An HTML user agent is a level 2 user agent if, additionally:

            * It allows the user to express all form field values
            specified in an HTML document and to (attempt to) submit the
            values as requests to information services.

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    2. Terms

        absolute URI
                a URI in absolute form; for example, as per [URL]

        anchor
                one of two ends of a hyperlink; typically, a phrase
                marked as an <A> element.

        base URI
                an absolute URI used in combination with a relative URI
                to determine another absolute URI.

        character
                An atom of information, for example a letter or a digit.
                Graphic characters have associated glyphs, whereas
                control characters have associated processing semantics.

        character encoding
        scheme
                A function whose domain is the set of sequences of
                octets, and whose range is the set of sequences of
                characters from a character repertoire; that is, a
                sequence of octets and a character encoding scheme
                determines a sequence of characters.

        character repertoire
                A finite set of characters; e.g. the range of a coded
                character set.

        code position
                An integer. A coded character set and a code position
                from its domain determine a character.

        coded character set
                A function whose domain is a subset of the integers and
                whose range is a character repertoire. That is, for some
                set of integers (usually of the form {0, 1, 2, ..., N}
                ), a coded character set and an integer in that set
                determine a character. Conversely, a character and a
                coded character set determine the character's code
                position (or, in rare cases, a few code positions).

        conforming HTML user
        agent
                A user agent that conforms to this specification in its
                processing of the Internet Media Type `text/html'.

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        data character
                Characters other than markup, which make up the content
                of elements.

        document character set
                a coded character set whose range includes all
                characters used in a document. Every SGML document has
                exactly one document character set. Numeric character
                references are resolved via the document character set.

        DTD
                document type definition. Rules that apply SGML to the
                markup of documents of a particular type, including a
                set of element and entity declarations. [SGML]

        element
                A component of the hierarchical structure defined by a
                document type definition; it is identified in a document
                instance by descriptive markup, usually a start-tag and
                end-tag. [SGML]

        end-tag
                Descriptive markup that identifies the end of an
                element. [SGML]

        entity
                data with an associated notation or interpretation; for
                example, a sequence of octets associated with an
                Internet Media Type. [SGML]

        fragment identifier
                the portion of an HREF attribute value following the `#'
                character which modifies the presentation of the
                destination of a hyperlink.

        form data set
                a sequence of name/value pairs; the names are given by
                an HTML document and the values are given by a user.

        HTML document
                An SGML document conforming to this document type
                definition.

        hyperlink
                a relationship between two anchors, called the head and
                the tail. The link goes from the tail to the head. The
                head and tail are also known as destination and source,
                respectively.

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        markup
                Syntactically delimited characters added to the data of
                a document to represent its structure. There are four
                different kinds of markup: descriptive markup (tags),
                references, markup declarations, and processing
                instructions. [SGML]

        may
                A document or user interface is conforming whether this
                statement applies or not.

        media type
                an Internet Media Type, as per [IMEDIA].

        message entity
                a head and body. The head is a collection of name/value
                fields, and the body is a sequence of octets. The head
                defines the content type and content transfer encoding
                of the body. [MIME]

        minimally conforming
        HTML user agent
                A user agent that conforms to this specification except
                for form processing. It may only process level 1 HTML
                documents.

        must
                Documents or user agents in conflict with this statement
                are not conforming.

        numeric character
        reference
                markup that refers to a character by its code position
                in the document character set.

        SGML document
                A sequence of characters organized physically as a set
                of entities and logically into a hierarchy of elements.
                An SGML document consists of data characters and markup;
                the markup describes the structure of the information
                and an instance of that structure. [SGML]

        shall
                If a document or user agent conflicts with this
                statement, it does not conform to this specification.

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        should
                If a document or user agent conflicts with this
                statement, undesirable results may occur in practice
                even though it conforms to this specification.

        start-tag
                Descriptive markup that identifies the start of an
                element and specifies its generic identifier and
                attributes. [SGML]

        syntax-reference
        character set
                A coded character set whose range includes all
                characters used for markup; e.g. name characters and
                delimiter characters.

        tag
                Markup that delimits an element. A tag includes a name
                which refers to an element declaration in the DTD, and
                may include attributes. [SGML]

        text entity
                A finite sequence of characters. A text entity typically
                takes the form of a sequence of octets with some
                associated character encoding scheme, transmitted over
                the network or stored in a file. [SGML]

        typical
                Typical processing is described for many elements. This
                is not a mandatory part of the specification but is
                given as guidance for designers and to help explain the
                uses for which the elements were intended.

        URI
                A Uniform Resource Identifier is a formatted string that
                serves as an identifier for a resource, typically on the
                Internet. URIs are used in HTML to identify the anchors
                of hyperlinks. URIs in common practice include Uniform
                Resource Locators (URLs)[URL] and Relative URLs
                [RELURL].

        user agent
                A component of a distributed system that presents an
                interface and processes requests on behalf of a user;
                for example, a www browser or a mail user agent.

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        WWW
                The World-Wide Web is a hypertext-based, distributed
                information system created by researchers at CERN in
                Switzerland. <URL:http://www.w3.org/>

    3. HTML as an Application of SGML

       HTML is an application of ISO 8879:1986 -- Standard Generalized
       Markup Language (SGML). SGML is a system for defining structured
       document types and markup languages to represent instances of those
       document types[SGML]. The public text -- DTD and SGML declaration --
       of the HTML document type definition are provided in 9, "HTML Public
       Text".

       The term "HTML" refers to both the document type defined here and the
       markup language for representing instances of this document type.

    3.1. SGML Documents

       An HTML document is an SGML document; that is, a sequence of
       characters organized physically into a set of entities, and logically
       as a hierarchy of elements.

       In the SGML specification, the first production of the SGML syntax
       grammar separates an SGML document into three parts: an SGML
       declaration, a prologue, and an instance. For the purposes of this
       specification, the prologue is a DTD. This DTD describes another
       grammar: the start symbol is given in the doctype declaration, the
       terminals are data characters and tags, and the productions are
       determined by the element declarations. The instance must conform to
       the DTD, that is, it must be in the language defined by this grammar.

       The SGML declaration determines the lexicon of the grammar. It
       specifies the document character set, which determines a character
       repertoire that contains all characters that occur in all text
       entities in the document, and the code positions associated with
       those characters.

       The SGML declaration also specifies the syntax-reference character
       set of the document, and a few other parameters that bind the
       abstract syntax of SGML to a concrete syntax. This concrete syntax
       determines how the sequence of characters of the document is mapped
       to a sequence of terminals in the grammar of the prologue.

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       For example, consider the following document:

        <!DOCTYPE html PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <title>Parsing Example</title>
        <p>Some text. <em>&#42;wow&#42;</em></p>

       An HTML user agent should use the SGML declaration that is given in
       9.5, "SGML Declaration for HTML". According to its document character
       set, `&#42;' refers to an asterisk character, `*'.

       The instance above is regarded as the following sequence of
       terminals:

            1. start-tag: TITLE

            2. data characters: "Parsing Example"

            3. end-tag: TITLE

            4. start-tag: P

            5. data characters "Some text."

            6. start-tag: EM

            7. data characters: "*wow*"

            8. end-tag: EM

            9. end-tag: P

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       The start symbol of the DTD grammar is HTML, and the productions are
       given in the public text identified by `-//IETF//DTD HTML 2.0//EN'
       (9.1, "HTML DTD"). The terminals above parse as:

           HTML
            |
            \-HEAD
            |  |
            |  \-TITLE
            |      |
            |      \-<TITLE>
            |      |
            |      \-"Parsing Example"
            |      |
            |      \-</TITLE>
            |
            \-BODY
              |
              \-P
                |
                \-<P>
                |
                \-"Some text. "
                |
                \-EM
                |  |
                |  \-<EM>
                |  |
                |  \-"*wow*"
                |  |
                |  \-</EM>
                |
                \-</P>

       Some of the elements are delimited explicitly by tags, while the
       boundaries of others are inferred. The <HTML> element contains a
       <HEAD> element and a <BODY> element. The <HEAD> contains <TITLE>,
       which is explicitly delimited by start- and end-tags.

    3.2. HTML Lexical Syntax

       SGML specifies an abstract syntax and a reference concrete syntax.
       Aside from certain quantities and capacities (e.g. the limit on the
       length of a name), all HTML documents use the reference concrete
       syntax. In particular, all markup characters are in the repertoire of
       [ISO-646]. Data characters are drawn from the document character set
       (see 6, "Characters, Words, and Paragraphs").

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       A complete discussion of SGML parsing, e.g. the mapping of a sequence
       of characters to a sequence of tags and data, is left to the SGML
       standard[SGML]. This section is only a summary.

    3.2.1. Data Characters

       Any sequence of characters that do not constitute markup (see 9.6
       "Delimiter Recognition" of [SGML]) are mapped directly to strings of
       data characters. Some markup also maps to data character strings.
       Numeric character references map to single-character strings, via the
       document character set. Each reference to one of the general entities
       defined in the HTML DTD maps to a single-character string.

       For example,

        abc&lt;def    => "abc","<","def"
        abc&#60;def   => "abc","<","def"

       The terminating semicolon on entity or numeric character references
       is only necessary when the character following the reference would
       otherwise be recognized as part of the name (see 9.4.5 "Reference
       End" in [SGML]).

        abc &lt def     => "abc ","<"," def"
        abc &#60 def    => "abc ","<"," def"

       An ampersand is only recognized as markup when it is followed by a
       letter or a `#' and a digit:

        abc & lt def    => "abc & lt def"
        abc &# 60 def    => "abc &# 60 def"

       A useful technique for translating plain text to HTML is to replace
       each '<', '&', and '>' by an entity reference or numeric character
       reference as follows:

                         ENTITY      NUMERIC
               CHARACTER REFERENCE   CHAR REF     CHARACTER DESCRIPTION
               --------- ----------  -----------  ---------------------
                 &       &amp;       &#38;        Ampersand
                 <       &lt;        &#60;        Less than
                 >       &gt;        &#62;        Greater than

            NOTE - There are SGML mechanisms, CDATA and RCDATA
            declared content, that allow most `<', `>', and `&'
            characters to be entered without the use of entity
            references. Because these mechanisms tend to be used and
            implemented inconsistently, and because they conflict

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            with techniques for reducing HTML to 7 bit ASCII for
            transport, they are deprecated in this version of HTML.
            See 5.5.2.1, "Example and Listing: XMP, LISTING".

    3.2.2. Tags

       Tags delimit elements such as headings, paragraphs, lists, character
       highlighting, and links. Most HTML elements are identified in a
       document as a start-tag, which gives the element name and attributes,
       followed by the content, followed by the end tag. Start-tags are
       delimited by `<' and `>'; end tags are delimited by `</' and `>'. An
       example is:

       <H1>This is a Heading</H1>

       Some elements only have a start-tag without an end-tag. For example,
       to create a line break, use the `<BR>' tag.  Additionally, the end
       tags of some other elements, such as Paragraph (`</P>'), List Item
       (`</LI>'), Definition Term (`</DT>'), and Definition Description
       (`</DD>') elements, may be omitted.

       The content of an element is a sequence of data character strings and
       nested elements. Some elements, such as anchors, cannot be nested.
       Anchors and character highlighting may be put inside other
       constructs. See the HTML DTD, 9.1, "HTML DTD" for full details.

          NOTE - The SGML declaration for HTML specifies SHORTTAG YES, which
          means that there are other valid syntaxes for tags, such as NET
          tags, `<EM/.../'; empty start tags, `<>'; and empty end-tags,
          `</>'. Until support for these idioms is widely deployed, their
          use is strongly discouraged.

    3.2.3. Names

       A name consists of a letter followed by letters, digits, periods, or
       hyphens. The length of a name is limited to 72 characters by the
       `NAMELEN' parameter in the SGML declaration for HTML, 9.5, "SGML
       Declaration for HTML". Element and attribute names are not case
       sensitive, but entity names are.  For example, `<BLOCKQUOTE>',
       `<BlockQuote>', and `<blockquote>' are equivalent, whereas `&amp;' is
       different from `&AMP;'.

       In a start-tag, the element name must immediately follow the tag open
       delimiter `<'.

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    3.2.4. Attributes

       In a start-tag, white space and attributes are allowed between the
       element name and the closing delimiter. An attribute specification
       typically consists of an attribute name, an equal sign, and a value,
       though some attribute specifications may be just a name token. White
       space is allowed around the equal sign.

       The value of the attribute may be either:

            * A string literal, delimited by single quotes or double
            quotes and not containing any occurrences of the delimiting
            character.

                NOTE - Some historical implementations consider any
                occurrence of the `>' character to signal the end of
                a tag. For compatibility with such implementations,
                when `>' appears in an attribute value, it should be
                represented with a numeric character reference. For
                example, `<IMG SRC="eq1.jpg" alt="a>b">' should be
                written `<IMG SRC="eq1.jpg" alt="a&#62;b">' or `<IMG
                SRC="eq1.jpg" alt="a&gt;b">'.

            * A name token (a sequence of letters, digits, periods, or
            hyphens). Name tokens are not case sensitive.

                NOTE - Some historical implementations allow any
                character except space or `>' in a name token.

       In this example, <img> is the element name, src is the attribute
       name, and `http://host/dir/file.gif' is the attribute value:

       <img src='http://host/dir/file.gif'>

       A useful technique for computing an attribute value literal for a
       given string is to replace each quote and white space character by an
       entity reference or numeric character reference as follows:

                         ENTITY      NUMERIC
               CHARACTER REFERENCE   CHAR REF     CHARACTER DESCRIPTION
               --------- ----------  -----------  ---------------------
                 HT                  &#9;         Tab
                 LF                  &#10;        Line Feed
                 CR                  &#13;        Carriage Return
                 SP                  &#32;        Space
                 "       &quot;      &#34;        Quotation mark
                 &       &amp;       &#38;        Ampersand

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       For example:

       <IMG SRC="image.jpg" alt="First &quot;real&quot; example">

       The `NAMELEN' parameter in the SGML declaration (9.5, "SGML
       Declaration for HTML") limits the length of an attribute value to
       1024 characters.

       Attributes such as ISMAP and COMPACT may be written using a minimized
       syntax (see 7.9.1.2 "Omitted Attribute Name" in [SGML]). The markup:

       <UL COMPACT="compact">

       can be written using a minimized syntax:

       <UL COMPACT>

       NOTE - Some historical implementations only understand the minimized
       syntax.

    3.2.5. Comments

       To include comments in an HTML document, use a comment declaration. A
       comment declaration consists of `<!' followed by zero or more
       comments followed by `>'. Each comment starts with `--' and includes
       all text up to and including the next occurrence of `--'. In a
       comment declaration, white space is allowed after each comment, but
       not before the first comment.  The entire comment declaration is
       ignored.

          NOTE - Some historical HTML implementations incorrectly consider
          any `>' character to be the termination of a comment.

       For example:

        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <HEAD>
        <TITLE>HTML Comment Example</TITLE>
        <!-- Id: html-sgml.sgm,v 1.5 1995/05/26 21:29:50 connolly Exp  -->
        <!-- another -- -- comment -->
        <!>
        </HEAD>
        <BODY>
        <p> <!- not a comment, just regular old data characters ->

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    3.3. HTML Public Text Identifiers

       To identify information as an HTML document conforming to this
       specification, each document must start with one of the following
       document type declarations.

       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">

       This document type declaration refers to the HTML DTD in 9.1, "HTML
       DTD".

          NOTE - If the body of a `text/html' message entity does not begin
          with a document type declaration, an HTML user agent should infer
          the above document type declaration.

       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Level 2//EN">

       This document type declaration also refers to the HTML DTD which
       appears in 9.1, "HTML DTD".

       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Level 1//EN">

       This document type declaration refers to the level 1 HTML DTD in 9.3,
       "Level 1 HTML DTD". Form elements must not occur in level 1
       documents.

       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Strict//EN">
       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Strict Level 1//EN">

       These two document type declarations refer to the HTML DTD in 9.2,
       "Strict HTML DTD" and 9.4, "Strict Level 1 HTML DTD". They refer to
       the more structurally rigid definition of HTML.

       HTML user agents may support other document types. In particular,
       they may support other formal public identifiers, or other document
       types altogether. They may support an internal declaration subset
       with supplemental entity, element, and other markup declarations.

    3.4. Example HTML Document

        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <HTML>
        <!-- Here's a good place to put a comment. -->
        <HEAD>
        <TITLE>Structural Example</TITLE>
        </HEAD><BODY>
        <H1>First Header</H1>
        <P>This is a paragraph in the example HTML file. Keep in mind

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        that the title does not appear in the document text, but that
        the header (defined by H1) does.</P>
        <OL>
        <LI>First item in an ordered list.
        <LI>Second item in an ordered list.
          <UL COMPACT>
          <LI> Note that lists can be nested;
          <LI> Whitespace may be used to assist in reading the
               HTML source.
          </UL>
        <LI>Third item in an ordered list.
        </OL>
        <P>This is an additional paragraph. Technically, end tags are
        not required for paragraphs, although they are allowed. You can
        include character highlighting in a paragraph. <EM>This sentence
        of the paragraph is emphasized.</EM> Note that the &lt;/P&gt;
        end tag has been omitted.
        <P>
        <IMG SRC ="triangle.xbm" alt="Warning: ">
        Be sure to read these <b>bold instructions</b>.
        </BODY></HTML>

    4. HTML as an Internet Media Type

       An HTML user agent allows users to interact with resources which have
       HTML representations. At a minimum, it must allow users to examine
       and navigate the content of HTML level 1 documents. HTML user agents
       should be able to preserve all formatting distinctions represented in
       an HTML document, and be able to simultaneously present resources
       referred to by IMG elements (they may ignore some formatting
       distinctions or IMG resources at the request of the user). Level 2
       HTML user agents should support form entry and submission.

    4.1. text/html media type

       This specification defines the Internet Media Type [IMEDIA] (formerly
       referred to as the Content Type [MIME]) called `text/html'. The
       following is to be registered with [IANA].

        Media Type name
                text

        Media subtype name
                html

        Required parameters
                none

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        Optional parameters
                level, charset

        Encoding considerations
                any encoding is allowed

        Security considerations
                see 10, "Security Considerations"

        The optional parameters are defined as follows:

        Level
                The level parameter specifies the feature set used in
                the document. The level is an integer number, implying
                that any features of same or lower level may be present
                in the document. Level 1 is all features defined in this
                specification except those that require the <FORM>
                element. Level 2 includes form processing. Level 2 is
                the default.

        Charset
                The charset parameter (as defined in section 7.1.1 of
                RFC 1521[MIME]) may be given to specify the character
                encoding scheme used to represent the HTML document as a
                sequence of octets. The default value is outside the
                scope of this specification; but for example, the
                default is `US-ASCII' in the context of MIME mail, and
                `ISO-8859-1' in the context of HTTP [HTTP].

    4.2. HTML Document Representation

       A message entity with a content type of `text/html' represents an
       HTML document, consisting of a single text entity. The `charset'
       parameter (whether implicit or explicit) identifies a character
       encoding scheme. The text entity consists of the characters
       determined by this character encoding scheme and the octets of the
       body of the message entity.

    4.2.1. Undeclared Markup Error Handling

       To facilitate experimentation and interoperability between
       implementations of various versions of HTML, the installed base of
       HTML user agents supports a superset of the HTML 2.0 language by
       reducing it to HTML 2.0: markup in the form of a start-tag or end-
       tag, whose generic identifier is not declared is mapped to nothing
       during tokenization. Undeclared attributes are treated similarly. The
       entire attribute specification of an unknown attribute (i.e., the
       unknown attribute and its value, if any) should be ignored. On the

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       other hand, references to undeclared entities should be treated as
       data characters.

       For example:

        <div class=chapter><h1>foo</h1><p>...</div>
          => <H1>,"foo",</H1>,<P>,"..."
        xxx <P ID=z23> yyy
          => "xxx ",<P>," yyy
        Let &alpha; &amp; &beta; be finite sets.
          => "Let &alpha; & &beta; be finite sets."

       Support for notifying the user of such errors is encouraged.

       Information providers are warned that this convention is not binding:
       unspecified behavior may result, as such markup does not conform to
       this specification.

    4.2.2. Conventional Representation of Newlines

       SGML specifies that a text entity is a sequence of records, each
       beginning with a record start character and ending with a record end
       character (code positions 10 and 13 respectively) (section 7.6.1,
       "Record Boundaries" in [SGML]).

       [MIME] specifies that a body of type `text/*' is a sequence of lines,
       each terminated by CRLF, that is, octets 13, 10.

       In practice, HTML documents are frequently represented and
       transmitted using an end of line convention that depends on the
       conventions of the source of the document; frequently, that
       representation consists of CR only, LF only, or a CR LF sequence.
       Hence the decoding of the octets will often result in a text entity
       with some missing record start and record end characters.

       Since there is no ambiguity, HTML user agents are encouraged to infer
       the missing record start and end characters.

       An HTML user agent should treat end of line in any of its variations
       as a word space in all contexts except preformatted text. Within
       preformatted text, an HTML user agent should treat any of the three
       common representations of end-of-line as starting a new line.

    5. Document Structure

       An HTML document is a tree of elements, including a head and body,
       headings, paragraphs, lists, etc. Form elements are discussed in 8,
       "Forms".

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    5.1. Document Element: HTML

       The HTML document element consists of a head and a body, much like a
       memo or a mail message. The head contains the title and optional
       elements. The body is a text flow consisting of paragraphs, lists,
       and other elements.

    5.2. Head: HEAD

       The head of an HTML document is an unordered collection of
       information about the document. For example:

        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <HEAD>
        <TITLE>Introduction to HTML</TITLE>
        </HEAD>
        ...

    5.2.1. Title: TITLE

       Every HTML document must contain a <TITLE> element.

       The title should identify the contents of the document in a global
       context. A short title, such as "Introduction" may be meaningless out
       of context. A title such as "Introduction to HTML Elements" is more
       appropriate.

          NOTE - The length of a title is not limited; however, long titles
          may be truncated in some applications. To minimize this
          possibility, titles should be fewer than 64 characters.

       A user agent may display the title of a document in a history list or
       as a label for the window displaying the document. This differs from
       headings (5.4, "Headings: H1 ... H6"), which are typically displayed
       within the body text flow.

    5.2.2. Base Address: BASE

       The optional <BASE> element provides a base address for interpreting
       relative URLs when the document is read out of context (see 7,
       "Hyperlinks"). The value of the HREF attribute must be an absolute
       URI.

    5.2.3. Keyword Index: ISINDEX

       The <ISINDEX> element indicates that the user agent should allow the
       user to search an index by giving keywords. See 7.5, "Queries and
       Indexes" for details.

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    5.2.4. Link: LINK

       The <LINK> element represents a hyperlink (see 7, "Hyperlinks").  Any
       number of LINK elements may occur in the <HEAD> element of an HTML
       document. It has the same attributes as the <A> element (see 5.7.3,
       "Anchor: A").

       The <LINK> element is typically used to indicate authorship, related
       indexes and glossaries, older or more recent versions, document
       hierarchy, associated resources such as style sheets, etc.

    5.2.5. Associated Meta-information: META

       The <META> element is an extensible container for use in identifying
       specialized document meta-information.  Meta-information has two main
       functions:

            * to provide a means to discover that the data set exists
            and how it might be obtained or accessed; and

            * to document the content, quality, and features of a data
            set, indicating its fitness for use.

       Each <META> element specifies a name/value pair. If multiple META
       elements are provided with the same name, their combined contents--
       concatenated as a comma-separated list--is the value associated with
       that name.

            NOTE - The <META> element should not be used where a
            specific element, such as <TITLE>, would be more
            appropriate. Rather than a <META> element with a URI as
            the value of the CONTENT attribute, use a <LINK>
            element.

       HTTP servers may read the content of the document <HEAD> to generate
       header fields corresponding to any elements defining a value for the
       attribute HTTP-EQUIV.

            NOTE - The method by which the server extracts document
            meta-information is unspecified and not mandatory. The
            <META> element only provides an extensible mechanism for
            identifying and embedding document meta-information --
            how it may be used is up to the individual server
            implementation and the HTML user agent.

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        Attributes of the META element:

        HTTP-EQUIV
                binds the element to an HTTP header field. An HTTP
                server may use this information to process the document.
                In particular, it may include a header field in the
                responses to requests for this document: the header name
                is taken from the HTTP-EQUIV attribute value, and the
                header value is taken from the value of the CONTENT
                attribute. HTTP header names are not case sensitive.

        NAME
                specifies the name of the name/value pair. If not
                present, HTTP-EQUIV gives the name.

        CONTENT
                specifies the value of the name/value pair.

        Examples

        If the document contains:

        <META HTTP-EQUIV="Expires"
              CONTENT="Tue, 04 Dec 1993 21:29:02 GMT">
        <meta http-equiv="Keywords" CONTENT="Fred">
        <META HTTP-EQUIV="Reply-to"
              content="fielding@ics.uci.edu (Roy Fielding)">
        <Meta Http-equiv="Keywords" CONTENT="Barney">

        then the server may include the following header fields:

        Expires: Tue, 04 Dec 1993 21:29:02 GMT
        Keywords: Fred, Barney
        Reply-to: fielding@ics.uci.edu (Roy Fielding)

        as part of the HTTP response to a `GET' or `HEAD' request for
        that document.

        An HTTP server must not use the <META> element to form an HTTP
        response header unless the HTTP-EQUIV attribute is present.

        An HTTP server may disregard any <META> elements that specify
        information controlled by the HTTP server, for example `Server',

        `Date', and `Last-modified'.

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    5.2.6. Next Id: NEXTID

       The <NEXTID> element is included for historical reasons only.  HTML
       documents should not contain <NEXTID> elements.

       The <NEXTID> element gives a hint for the name to use for a new <A>
       element when editing an HTML document. It should be distinct from all
       NAME attribute values on <A> elements. For example:

       <NEXTID N=Z27>

    5.3. Body: BODY

       The <BODY> element contains the text flow of the document, including
       headings, paragraphs, lists, etc.

       For example:

        <BODY>
        <h1>Important Stuff</h1>
        <p>Explanation about important stuff...
        </BODY>

    5.4. Headings: H1 ... H6

       The six heading elements, <H1> through <H6>, denote section headings.
       Although the order and occurrence of headings is not constrained by
       the HTML DTD, documents should not skip levels (for example, from H1
       to H3), as converting such documents to other representations is
       often problematic.

       Example of use:

        <H1>This is a heading</H1>
        Here is some text
        <H2>Second level heading</H2>
        Here is some more text.

        Typical renderings are:

        H1
                Bold, very-large font, centered. One or two blank lines
                above and below.

        H2
                Bold, large font, flush-left. One or two blank lines
                above and below.

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        H3
                Italic, large font, slightly indented from the left
                margin. One or two blank lines above and below.

        H4
                Bold, normal font, indented more than H3. One blank line
                above and below.

        H5
                Italic, normal font, indented as H4. One blank line
                above.

        H6
                Bold, indented same as normal text, more than H5. One
                blank line above.

    5.5. Block Structuring Elements

       Block structuring elements include paragraphs, lists, and block
       quotes. They must not contain heading elements, but they may contain
       phrase markup, and in some cases, they may be nested.

    5.5.1. Paragraph: P

       The <P> element indicates a paragraph. The exact indentation, leading
       space, etc. of a paragraph is not specified and may be a function of
       other tags, style sheets, etc.

       Typically, paragraphs are surrounded by a vertical space of one line
       or half a line. The first line in a paragraph is indented in some
       cases.

       Example of use:

        <H1>This Heading Precedes the Paragraph</H1>
        <P>This is the text of the first paragraph.
        <P>This is the text of the second paragraph. Although you do not
        need to start paragraphs on new lines, maintaining this
        convention facilitates document maintenance.</P>
        <P>This is the text of a third paragraph.</P>

    5.5.2. Preformatted Text: PRE

       The <PRE> element represents a character cell block of text and is
       suitable for text that has been formatted for a monospaced font.

       The <PRE> tag may be used with the optional WIDTH attribute. The
       WIDTH attribute specifies the maximum number of characters for a line

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       and allows the HTML user agent to select a suitable font and
       indentation.

       Within preformatted text:

            * Line breaks within the text are rendered as a move to the
            beginning of the next line.

                NOTE - References to the "beginning of a new line"
                do not imply that the renderer is forbidden from
                using a constant left indent for rendering
                preformatted text. The left indent may be
                constrained by the width required.

            * Anchor elements and phrase markup may be used.

                NOTE - Constraints on the processing of <PRE>
                content may limit or prevent the ability of the HTML
                user agent to faithfully render phrase markup.

            * Elements that define paragraph formatting (headings,
            address, etc.) must not be used.

                NOTE - Some historical documents contain <P> tags in
                <PRE> elements. User agents are encouraged to treat
                this as a line break. A <P> tag followed by a
                newline character should produce only one line
                break, not a line break plus a blank line.

            * The horizontal tab character (code position 9 in the HTML
            document character set) must be interpreted as the smallest
            positive nonzero number of spaces which will leave the
            number of characters so far on the line as a multiple of 8.
            Documents should not contain tab characters, as they are not
            supported consistently.

        Example of use:

        <PRE>
        Line 1.
               Line 2 is to the right of line 1.     <a href="abc">abc</a>
               Line 3 aligns with line 2.            <a href="def">def</a>
        </PRE>

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    5.5.2.1. Example and Listing: XMP, LISTING

       The <XMP> and <LISTING> elements are similar to the <PRE> element,
       but they have a different syntax. Their content is declared as CDATA,
       which means that no markup except the end-tag open delimiter-in-
       context is recognized (see 9.6 "Delimiter Recognition" of [SGML]).

          NOTE - In a previous draft of the HTML specification, the syntax
          of <XMP> and <LISTING> elements allowed closing tags to be treated
          as data characters, as long as the tag name was not <XMP> or
          <LISTING>, respectively.

       Since CDATA declared content has a number of unfortunate interactions
       with processing techniques and tends to be used and implemented
       inconsistently, HTML documents should not contain <XMP> nor <LISTING>
       elements -- the <PRE> tag is more expressive and more consistently
       supported.

       The <LISTING> element should be rendered so that at least 132
       characters fit on a line. The <XMP> element should be rendered so
       that at least 80 characters fit on a line but is otherwise identical
       to the <LISTING> element.

          NOTE - In a previous draft, HTML included a <PLAINTEXT> element
          that is similar to the <LISTING> element, except that there is no
          closing tag: all characters after the <PLAINTEXT> start-tag are
          data.

    5.5.3. Address: ADDRESS

       The <ADDRESS> element contains such information as address, signature
       and authorship, often at the beginning or end of the body of a
       document.

       Typically, the <ADDRESS> element is rendered in an italic typeface
       and may be indented.

       Example of use:

        <ADDRESS>
        Newsletter editor<BR>
        J.R. Brown<BR>
        JimquickPost News, Jimquick, CT 01234<BR>
        Tel (123) 456 7890
        </ADDRESS>

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    5.5.4. Block Quote: BLOCKQUOTE

       The <BLOCKQUOTE> element contains text quoted from another source.

       A typical rendering might be a slight extra left and right indent,
       and/or italic font. The <BLOCKQUOTE> typically provides space above
       and below the quote.

       Single-font rendition may reflect the quotation style of Internet
       mail by putting a vertical line of graphic characters, such as the
       greater than symbol (>), in the left margin.

       Example of use:

        I think the play ends
        <BLOCKQUOTE>
        <P>Soft you now, the fair Ophelia. Nymph, in thy orisons, be all
        my sins remembered.
        </BLOCKQUOTE>
        but I am not sure.

    5.6. List Elements

       HTML includes a number of list elements. They may be used in
       combination; for example, a <OL> may be nested in an <LI> element of
       a <UL>.

       The COMPACT attribute suggests that a compact rendering be used.

    5.6.1. Unordered List: UL, LI

       The <UL> represents a list of items -- typically rendered as a
       bulleted list.

       The content of a <UL> element is a sequence of <LI> elements.  For
       example:

        <UL>
        <LI>First list item
        <LI>Second list item
         <p>second paragraph of second item
        <LI>Third list item
        </UL>

    5.6.2. Ordered List: OL

       The <OL> element represents an ordered list of items, sorted by
       sequence or order of importance. It is typically rendered as a

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       numbered list.

       The content of a <OL> element is a sequence of <LI> elements.  For
       example:

        <OL>
        <LI>Click the Web button to open URI window.
        <LI>Enter the URI number in the text field of the Open URI
        window. The Web document you specified is displayed.
          <ol>
           <li>substep 1
           <li>substep 2
          </ol>
        <LI>Click highlighted text to move from one link to another.
        </OL>

    5.6.3. Directory List: DIR

       The <DIR> element is similar to the <UL> element. It represents a
       list of short items, typically up to 20 characters each. Items in a
       directory list may be arranged in columns, typically 24 characters
       wide.

       The content of a <DIR> element is a sequence of <LI> elements.
       Nested block elements are not allowed in the content of <DIR>
       elements. For example:

        <DIR>
        <LI>A-H<LI>I-M
        <LI>M-R<LI>S-Z
        </DIR>

    5.6.4. Menu List: MENU

       The <MENU> element is a list of items with typically one line per
       item. The menu list style is typically more compact than the style of
       an unordered list.

       The content of a <MENU> element is a sequence of <LI> elements.
       Nested block elements are not allowed in the content of <MENU>
       elements. For example:

        <MENU>
        <LI>First item in the list.
        <LI>Second item in the list.
        <LI>Third item in the list.
        </MENU>

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    5.6.5. Definition List: DL, DT, DD

       A definition list is a list of terms and corresponding definitions.
       Definition lists are typically formatted with the term flush-left and
       the definition, formatted paragraph style, indented after the term.

       The content of a <DL> element is a sequence of <DT> elements and/or
       <DD> elements, usually in pairs. Multiple <DT> may be paired with a
       single <DD> element. Documents should not contain multiple
       consecutive <DD> elements.

       Example of use:

        <DL>
        <DT>Term<DD>This is the definition of the first term.
        <DT>Term<DD>This is the definition of the second term.
        </DL>

       If the DT term does not fit in the DT column (typically one third of
       the display area), it may be extended across the page with the DD
       section moved to the next line, or it may be wrapped onto successive
       lines of the left hand column.

       The optional COMPACT attribute suggests that a compact rendering be
       used, because the list items are small and/or the entire list is
       large.

       Unless the COMPACT attribute is present, an HTML user agent may leave
       white space between successive DT, DD pairs. The COMPACT attribute
       may also reduce the width of the left-hand (DT) column.

        <DL COMPACT>
        <DT>Term<DD>This is the first definition in compact format.
        <DT>Term<DD>This is the second definition in compact format.
        </DL>

    5.7. Phrase Markup

       Phrases may be marked up according to idiomatic usage, typographic
       appearance, or for use as hyperlink anchors.

       User agents must render highlighted phrases distinctly from plain
       text. Additionally, <EM> content must be rendered as distinct from
       <STRONG> content, and <B> content must rendered as distinct from <I>
       content.

       Phrase elements may be nested within the content of other phrase
       elements; however, HTML user agents may render nested phrase elements

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       indistinctly from non-nested elements:

       plain <B>bold <I>italic</I></B> may be rendered
       the same as plain <B>bold </B><I>italic</I>

    5.7.1. Idiomatic Elements

       Phrases may be marked up to indicate certain idioms.

          NOTE - User agents may support the <DFN> element, not included in
          this specification, as it has been deployed to some extent. It is
          used to indicate the defining instance of a term, and it is
          typically rendered in italic or bold italic.

    5.7.1.1. Citation: CITE

          The <CITE> element is used to indicate the title of a book or
          other citation. It is typically rendered as italics. For example:

          He just couldn't get enough of <cite>The Grapes of Wrath</cite>.

    5.7.1.2. Code: CODE

          The <CODE> element indicates an example of code, typically
          rendered in a mono-spaced font. The <CODE> element is intended for
          short words or phrases of code; the <PRE> block structuring
          element (5.5.2, "Preformatted Text: PRE") is more appropriate
           for multiple-line listings. For example:

          The expression <code>x += 1</code>
          is short for <code>x = x + 1</code>.

    5.7.1.3. Emphasis: EM

          The <EM> element indicates an emphasized phrase, typically
          rendered as italics. For example:

          A singular subject <em>always</em> takes a singular verb.

    5.7.1.4. Keyboard: KBD

          The <KBD> element indicates text typed by a user, typically
          rendered in a mono-spaced font. This is commonly used in
          instruction manuals. For example:

          Enter <kbd>FIND IT</kbd> to search the database.

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    5.7.1.5. Sample: SAMP

          The <SAMP> element indicates a sequence of literal characters,
          typically rendered in a mono-spaced font. For example:

          The only word containing the letters <samp>mt</samp> is dreamt.

    5.7.1.6. Strong Emphasis: STRONG

          The <STRONG> element indicates strong emphasis, typically rendered
          in bold. For example:

          <strong>STOP</strong>, or I'll say "<strong>STOP</strong>" again!

    5.7.1.7. Variable: VAR

          The <VAR> element indicates a placeholder variable, typically
          rendered as italic. For example:

          Type <SAMP>html-check <VAR>file</VAR> | more</SAMP>
          to check <VAR>file</VAR> for markup errors.

    5.7.2. Typographic Elements

          Typographic elements are used to specify the format of marked
          text.

          Typical renderings for idiomatic elements may vary between user
          agents. If a specific rendering is necessary -- for example, when
          referring to a specific text attribute as in "The italic parts are
          mandatory" -- a typographic element can be used to ensure that the
          intended typography is used where possible.

          NOTE - User agents may support some typographic elements not
          included in this specification, as they have been deployed to some
          extent. The <STRIKE> element indicates horizontal line through the
          characters, and the <U> element indicates an underline.

    5.7.2.1. Bold: B

       The <B> element indicates bold text. Where bold typography is
       unavailable, an alternative representation may be used.

    5.7.2.2. Italic: I

       The <I> element indicates italic text. Where italic typography is
       unavailable, an alternative representation may be used.

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    5.7.2.3. Teletype: TT

       The <TT> element indicates teletype (monospaced )text. Where a
       teletype font is unavailable, an alternative representation may be
       used.

    5.7.3. Anchor: A

       The <A> element indicates a hyperlink anchor (see 7, "Hyperlinks").
       At least one of the NAME and HREF attributes should be present.
       Attributes of the <A> element:

        HREF
                gives the URI of the head anchor of a hyperlink.

        NAME
                gives the name of the anchor, and makes it available as
                a head of a hyperlink.

        TITLE
                suggests a title for the destination resource --
                advisory only. The TITLE attribute may be used:

                    * for display prior to accessing the destination
                    resource, for example, as a margin note or on a
                    small box while the mouse is over the anchor, or
                    while the document is being loaded;

                    * for resources that do not include a title, such as
                    graphics, plain text and Gopher menus, for use as a
                    window title.

        REL
                The REL attribute gives the relationship(s) described by
                the hyperlink. The value is a whitespace separated list
                of relationship names. The semantics of link
                relationships are not specified in this document.

        REV
                same as the REL attribute, but the semantics of the
                relationship are in the reverse direction. A link from A
                to B with REL="X" expresses the same relationship as a
                link from B to A with REV="X". An anchor may have both
                REL and REV attributes.

        URN
                specifies a preferred, more persistent identifier for
                the head anchor of the hyperlink. The syntax and

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                semantics of the URN attribute are not yet specified.

        METHODS
                specifies methods to be used in accessing the
                destination, as a whitespace-separated list of names.
                The set of applicable names is a function of the scheme
                of the URI in the HREF attribute. For similar reasons as
                for the TITLE attribute, it may be useful to include the
                information in advance in the link. For example, the
                HTML user agent may chose a different rendering as a
                function of the methods allowed; for example, something
                that is searchable may get a different icon.

    5.8. Line Break: BR

       The <BR> element specifies a line break between words (see 6,
       "Characters, Words, and Paragraphs"). For example:

        <P> Pease porridge hot<BR>
        Pease porridge cold<BR>
        Pease porridge in the pot<BR>
        Nine days old.

    5.9. Horizontal Rule: HR

       The <HR> element is a divider between sections of text; typically a
       full width horizontal rule or equivalent graphic.  For example:

        <HR>
        <ADDRESS>February 8, 1995, CERN</ADDRESS>
        </BODY>

    5.10. Image: IMG

       The <IMG> element refers to an image or icon via a hyperlink (see
       7.3, "Simultaneous Presentation of Image Resources").

       HTML user agents may process the value of the ALT attribute as an
       alternative to processing the image resource indicated by the SRC
       attribute.

          NOTE - Some HTML user agents can process graphics linked via
          anchors, but not <IMG> graphics. If a graphic is essential, it
          should be referenced from an <A> element rather than an <IMG>
          element. If the graphic is not essential, then the <IMG> element
          is appropriate.

       Attributes of the <IMG> element:

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        ALIGN
                alignment of the image with respect to the text
                baseline.

                    * `TOP' specifies that the top of the image aligns
                    with the tallest item on the line containing the
                    image.

                    * `MIDDLE' specifies that the center of the image
                    aligns with the baseline of the line containing the
                    image.

                    * `BOTTOM' specifies that the bottom of the image
                    aligns with the baseline of the line containing the
                    image.

        ALT
                text to use in place of the referenced image resource,
                for example due to processing constraints or user
                preference.

        ISMAP
                indicates an image map (see 7.6, "Image Maps").

        SRC
                specifies the URI of the image resource.

                    NOTE - In practice, the media types of image
                    resources are limited to a few raster graphic
                    formats: typically `image/gif', `image/jpeg'. In
                    particular, `text/html' resources are not
                    intended to be used as image resources.

        Examples of use:

        <IMG SRC="triangle.xbm" ALT="Warning:"> Be sure
        to read these instructions.

        <a href="http://machine/htbin/imagemap/sample">
        <IMG SRC="sample.xbm" ISMAP>
        </a>

    6. Characters, Words, and Paragraphs

       An HTML user agent should present the body of an HTML document as a
       collection of typeset paragraphs and preformatted text.  Except for
       preformatted elements (<PRE>, <XMP>, <LISTING>, <TEXTAREA>), each
       block structuring element is regarded as a paragraph by taking the

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       data characters in its content and the content of its descendant
       elements, concatenating them, and splitting the result into words,
       separated by space, tab, or record end characters (and perhaps hyphen
       characters). The sequence of words is typeset as a paragraph by
       breaking it into lines.

    6.1. The HTML Document Character Set

       The document character set specified in 9.5, "SGML Declaration for
       HTML" must be supported by HTML user agents. It includes the graphic
       characters of Latin Alphabet No. 1, or simply Latin-1.  Latin-1
       comprises 191 graphic characters, including the alphabets of most
       Western European languages.

          NOTE - Use of the non-breaking space and soft hyphen indicator
          characters is discouraged because support for them is not widely
          deployed.

          NOTE - To support non-western writing systems, a larger character
          repertoire will be specified in a future version of HTML. The
          document character set will be [ISO-10646], or some subset that
          agrees with [ISO-10646]; in particular, all numeric character
          references must use code positions assigned by [ISO-10646].

       In SGML applications, the use of control characters is limited in
       order to maximize the chance of successful interchange over
       heterogeneous networks and operating systems. In the HTML document
       character set only three control characters are allowed: Horizontal
       Tab, Carriage Return, and Line Feed (code positions 9, 13, and 10).

       The HTML DTD references the Added Latin 1 entity set, to allow
       mnemonic representation of selected Latin 1 characters using only the
       widely supported ASCII character repertoire. For example:

       Kurt G&ouml;del was a famous logician and mathematician.

       See 9.7.2, "ISO Latin 1 Character Entity Set" for a table of the
       "Added Latin 1" entities, and 13, "The HTML Coded Character Set" for
       a table of the code positions of [ISO 8859-1] and the control
       characters in the HTML document character set.

    7. Hyperlinks

       In addition to general purpose elements such as paragraphs and lists,
       HTML documents can express hyperlinks. An HTML user agent allows the
       user to navigate these hyperlinks.

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       A hyperlink is a relationship between two anchors, called the head
       and the tail of the hyperlink[DEXTER]. Anchors are identified by an
       anchor address: an absolute Uniform Resource Identifier (URI),
       optionally followed by a '#' and a sequence of characters called a
       fragment identifier. For example:

       http://www.w3.org/hypertext/WWW/TheProject.html
       http://www.w3.org/hypertext/WWW/TheProject.html#z31

       In an anchor address, the URI refers to a resource; it may be used in
       a variety of information retrieval protocols to obtain an entity that
       represents the resource, such as an HTML document. The fragment
       identifier, if present, refers to some view on, or portion of the
       resource.

       Each of the following markup constructs indicates the tail anchor of
       a hyperlink or set of hyperlinks:

            * <A> elements with HREF present.

            * <LINK> elements.

            * <IMG> elements.

            * <INPUT> elements with the SRC attribute present.

            * <ISINDEX> elements.

            * <FORM> elements with `METHOD=GET'.

       These markup constructs refer to head anchors by a URI, either
       absolute or relative, or a fragment identifier, or both.

       In the case of a relative URI, the absolute URI in the address of the
       head anchor is the result of combining the relative URI with a base
       absolute URI as in [RELURL]. The base document is taken from the
       document's <BASE> element, if present; else, it is determined as in
       [RELURL].

    7.1. Accessing Resources

       Once the address of the head anchor is determined, the user agent may
       obtain a representation of the resource.

       For example, if the base URI is `http://host/x/y.html' and the
       document contains:

       <img src="../icons/abc.gif">

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       then the user agent uses the URI `http://host/icons/abc.gif' to
       access the resource, as in [URL]..

    7.2. Activation of Hyperlinks

       An HTML user agent allows the user to navigate the content of the
       document and request activation of hyperlinks denoted by <A>
       elements. HTML user agents should also allow activation of <LINK>
       element hyperlinks.

       To activate a link, the user agent obtains a representation of the
       resource identified in the address of the head anchor. If the
       representation is another HTML document, navigation may begin again
       with this new document.

    7.3. Simultaneous Presentation of Image Resources

       An HTML user agent may activate hyperlinks indicated by <IMG> and
       <INPUT> elements concurrently with processing the document; that is,
       image hyperlinks may be processed without explicit request by the
       user. Image resources should be embedded in the presentation at the
       point of the tail anchor, that is the <IMG> or <INPUT> element.

       <LINK> hyperlinks may also be processed without explicit user
       request; for example, style sheet resources may be processed before
       or during the processing of the document.

    7.4. Fragment Identifiers

       Any characters following a `#' character in a hypertext address
       constitute a fragment identifier. In particular, an address of the
       form `#fragment' refers to an anchor in the same document.

       The meaning of fragment identifiers depends on the media type of the
       representation of the anchor's resource. For `text/html'
       representations, it refers to the <A> element with a NAME attribute
       whose value is the same as the fragment identifier.  The matching is
       case sensitive. The document should have exactly one such element.
       The user agent should indicate the anchor element, for example by
       scrolling to and/or highlighting the phrase.

       For example, if the base URI is `http://host/x/y.html' and the user
       activated the link denoted by the following markup:

       <p> See: <a href="app1.html#bananas">appendix 1</a>
       for more detail on bananas.

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       Then the user agent accesses the resource identified by
       `http://host/x/app1.html'. Assuming the resource is represented using
       the `text/html' media type, the user agent must locate the <A>
       element whose NAME attribute is `bananas' and begin navigation there.

    7.5. Queries and Indexes

       The <ISINDEX> element represents a set of hyperlinks. The user can
       choose from the set by providing keywords to the user agent.  The
       user agent computes the head URI by appending `?' and the keywords to
       the base URI. The keywords are escaped according to [URL] and joined
       by `+'. For example, if a document contains:

        <BASE HREF="http://host/index">
        <ISINDEX>

        and the user provides the keywords `apple' and `berry', then the
        user agent must access the resource
        `http://host/index?apple+berry'.

        <FORM> elements with `METHOD=GET' also represent sets of
        hyperlinks. See 8.2.2, "Query Forms: METHOD=GET" for details.

    7.6. Image Maps

       If the ISMAP attribute is present on an <IMG> element, the <IMG>
       element must be contained in an <A> element with an HREF present.
       This construct represents a set of hyperlinks. The user can choose
       from the set by choosing a pixel of the image. The user agent
       computes the head URI by appending `?' and the x and y coordinates of
       the pixel to the URI given in the <A> element.  For example, if a
       document contains:

       <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
       <head><title>ImageMap Example</title>
       <BASE HREF="http://host/index"></head>
       <body>
       <p> Choose any of these icons:<br>
       <a href="/cgi-bin/imagemap"><img ismap src="icons.gif"></a>

       and the user chooses the upper-leftmost pixel, the chosen
       hyperlink is the one with the URI
       `http://host/cgi-bin/imagemap?0,0'.

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    8. Forms

       A form is a template for a form data set and an associated
       method and action URI. A form data set is a sequence of
       name/value pair fields. The names are specified on the NAME
       attributes of form input elements, and the values are given
       initial values by various forms of markup and edited by the
       user. The resulting form data set is used to access an
       information service as a function of the action and method.

       Forms elements can be mixed in with document structuring
       elements. For example, a <PRE> element may contain a <FORM>
       element, or a <FORM> element may contain lists which contain
       <INPUT> elements. This gives considerable flexibility in
       designing the layout of forms.

       Form processing is a level 2 feature.

    8.1. Form Elements

    8.1.1. Form: FORM

       The <FORM> element contains a sequence of input elements, along
       with document structuring elements. The attributes are:

        ACTION
                specifies the action URI for the form. The action URI of
                a form defaults to the base URI of the document (see 7,
                "Hyperlinks").

        METHOD
                selects a method of accessing the action URI. The set of
                applicable methods is a function of the scheme of the
                action URI of the form. See 8.2.2, "Query Forms:
                METHOD=GET" and 8.2.3, "Forms with Side-Effects:
                METHOD=POST".

        ENCTYPE
                specifies the media type used to encode the name/value
                pairs for transport, in case the protocol does not
                itself impose a format. See 8.2.1, "The form-urlencoded
                Media Type".

    8.1.2. Input Field: INPUT

       The <INPUT> element represents a field for user input. The TYPE
       attribute discriminates between several variations of fields.

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       The <INPUT> element has a number of attributes. The set of applicable
       attributes depends on the value of the TYPE attribute.

    8.1.2.1. Text Field: INPUT TYPE=TEXT

       The default value of the TYPE attribute is `TEXT', indicating a
       single line text entry field. (Use the <TEXTAREA> element for multi-
       line text fields.)

       Required attributes are:

        NAME
                name for the form field corresponding to this element.

        The optional attributes are:

        MAXLENGTH
                constrains the number of characters that can be entered
                into a text input field. If the value of MAXLENGTH is
                greater the the value of the SIZE attribute, the field
                should scroll appropriately. The default number of
                characters is unlimited.

        SIZE
                specifies the amount of display space allocated to this
                input field according to its type. The default depends
                on the user agent.

        VALUE
                The initial value of the field.

        For example:

    <p>Street Address: <input name=street><br>
    Postal City code: <input name=city size=16 maxlength=16><br>
    Zip Code: <input name=zip size=10 maxlength=10 value="99999-9999"><br>

    8.1.2.2. Password Field: INPUT TYPE=PASSWORD

       An <INPUT> element with `TYPE=PASSWORD' is a text field as above,
       except that the value is obscured as it is entered. (see also: 10,
       "Security Considerations").

       For example:

    <p>Name: <input name=login> Password: <input type=password name=passwd>

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    8.1.2.3. Check Box: INPUT TYPE=CHECKBOX

       An <INPUT> element with `TYPE=CHECKBOX' represents a boolean choice.
       A set of such elements with the same name represents an n-of-many
       choice field. Required attributes are:

        NAME
                symbolic name for the form field corresponding to this
                element or group of elements.

        VALUE
                The portion of the value of the field contributed by
                this element.

        Optional attributes are:

        CHECKED
                indicates that the initial state is on.

        For example:

      <p>What flavors do you like?
      <input type=checkbox name=flavor value=vanilla>Vanilla<br>
      <input type=checkbox name=flavor value=strawberry>Strawberry<br>
      <input type=checkbox name=flavor value=chocolate checked>Chocolate<br>

    8.1.2.4. Radio Button: INPUT TYPE=RADIO

       An <INPUT> element with `TYPE=RADIO' represents a boolean choice. A
       set of such elements with the same name represents a 1-of-many choice
       field. The NAME and VALUE attributes are required as for check boxes.
       Optional attributes are:

        CHECKED
                indicates that the initial state is on.
       At all times, exactly one of the radio buttons in a set is checked.
       If none of the <INPUT> elements of a set of radio buttons specifies
       `CHECKED', then the user agent must check the first radio button of
       the set initially.

       For example:

        <p>Which is your favorite?
        <input type=radio name=flavor value=vanilla>Vanilla<br>
        <input type=radio name=flavor value=strawberry>Strawberry<br>
        <input type=radio name=flavor value=chocolate>Chocolate<br>

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    8.1.2.5. Image Pixel: INPUT TYPE=IMAGE

       An <INPUT> element with `TYPE=IMAGE' specifies an image resource to
       display, and allows input of two form fields: the x and y coordinate
       of a pixel chosen from the image. The names of the fields are the
       name of the field with `.x' and `.y' appended.  `TYPE=IMAGE' implies
       `TYPE=SUBMIT' processing; that is, when a pixel is chosen, the form
       as a whole is submitted.

       The NAME attribute is required as for other input fields. The SRC
       attribute is required and the ALIGN is optional as for the <IMG>
       element (see 5.10, "Image: IMG").

       For example:

        <p>Choose a point on the map:
        <input type=image name=point src="map.gif">

    8.1.2.6. Hidden Field: INPUT TYPE=HIDDEN

       An <INPUT> element with `TYPE=HIDDEN' represents a hidden field.The
       user does not interact with this field; instead, the VALUE attribute
       specifies the value of the field. The NAME and VALUE attributes are
       required.

       For example:

       <input type=hidden name=context value="l2k3j4l2k3j4l2k3j4lk23">

    8.1.2.7. Submit Button: INPUT TYPE=SUBMIT

       An <INPUT> element with `TYPE=SUBMIT' represents an input option,
       typically a button, that instructs the user agent to submit the form.
       Optional attributes are:

        NAME
                indicates that this element contributes a form field
                whose value is given by the VALUE attribute. If the NAME
                attribute is not present, this element does not
                contribute a form field.

        VALUE
                indicates a label for the input (button).

        You may submit this request internally:
        <input type=submit name=recipient value=internal><br>
        or to the external world:
        <input type=submit name=recipient value=world>

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    8.1.2.8. Reset Button: INPUT TYPE=RESET

       An <INPUT> element with `TYPE=RESET' represents an input option,
       typically a button, that instructs the user agent to reset the form's
       fields to their initial states. The VALUE attribute, if present,
       indicates a label for the input (button).

       When you are finished, you may submit this request:
       <input type=submit><br>
       You may clear the form and start over at any time: <input type=reset>

    8.1.3. Selection: SELECT

       The <SELECT> element constrains the form field to an enumerated list
       of values. The values are given in <OPTION> elements.  Attributes
       are:

        MULTIPLE
                indicates that more than one option may be included in
                the value.

        NAME
                specifies the name of the form field.

        SIZE
                specifies the number of visible items. Select fields of
                size one are typically pop-down menus, whereas select
                fields with size greater than one are typically lists.

        For example:

        <SELECT NAME="flavor">
        <OPTION>Vanilla
        <OPTION>Strawberry
        <OPTION value="RumRasin">Rum and Raisin
        <OPTION selected>Peach and Orange
        </SELECT>

       The initial state has the first option selected, unless a SELECTED
       attribute is present on any of the <OPTION> elements.

    8.1.3.1. Option: OPTION

       The Option element can only occur within a Select element. It
       represents one choice, and has the following attributes:

        SELECTED
                Indicates that this option is initially selected.

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        VALUE
                indicates the value to be returned if this option is
                chosen. The field value defaults to the content of the
                <OPTION> element.

       The content of the <OPTION> element is presented to the user to
       represent the option. It is used as a returned value if the VALUE
       attribute is not present.

    8.1.4. Text Area: TEXTAREA

       The <TEXTAREA> element represents a multi-line text field.
       Attributes are:

        COLS
                the number of visible columns to display for the text
                area, in characters.

        NAME
                Specifies the name of the form field.

        ROWS
                The number of visible rows to display for the text area,
                in characters.

        For example:

        <TEXTAREA NAME="address" ROWS=6 COLS=64>
        HaL Computer Systems
        1315 Dell Avenue
        Campbell, California 95008
        </TEXTAREA>

       The content of the <TEXTAREA> element is the field's initial value.

       Typically, the ROWS and COLS attributes determine the visible
       dimension of the field in characters. The field is typically rendered
       in a fixed-width font. HTML user agents should allow text to extend
       beyond these limits by scrolling as needed.

    8.2. Form Submission

       An HTML user agent begins processing a form by presenting the
       document with the fields in their initial state. The user is allowed
       to modify the fields, constrained by the field type etc.  When the
       user indicates that the form should be submitted (using a submit
       button or image input), the form data set is processed according to
       its method, action URI and enctype.

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       When there is only one single-line text input field in a form, the
       user agent should accept Enter in that field as a request to submit
       the form.

    8.2.1. The form-urlencoded Media Type

       The default encoding for all forms is `application/x-www-form-
       urlencoded'. A form data set is represented in this media type as
       follows:

            1. The form field names and values are escaped: space
            characters are replaced by `+', and then reserved characters
            are escaped as per [URL]; that is, non-alphanumeric
            characters are replaced by `%HH', a percent sign and two
            hexadecimal digits representing the ASCII code of the
            character. Line breaks, as in multi-line text field values,
            are represented as CR LF pairs, i.e. `%0D%0A'.

            2. The fields are listed in the order they appear in the
            document with the name separated from the value by `=' and
            the pairs separated from each other by `&'. Fields with null
            values may be omitted. In particular, unselected radio
            buttons and checkboxes should not appear in the encoded
            data, but hidden fields with VALUE attributes present
            should.

                NOTE - The URI from a query form submission can be
                used in a normal anchor style hyperlink.
                Unfortunately, the use of the `&' character to
                separate form fields interacts with its use in SGML
                attribute values as an entity reference delimiter.
                For example, the URI `http://host/?x=1&y=2' must be
                written `<a href="http://host/?x=1&#38;y=2"' or `<a
                href="http://host/?x=1&amp;y=2">'.

                HTTP server implementors, and in particular, CGI
                implementors are encouraged to support the use of
                `;' in place of `&' to save users the trouble of
                escaping `&' characters this way.

    8.2.2. Query Forms: METHOD=GET

       If the processing of a form is idempotent (i.e. it has no lasting
       observable effect on the state of the world), then the form method
       should be `GET'. Many database searches have no visible side-effects
       and make ideal applications of query forms.

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       To process a form whose action URL is an HTTP URL and whose method is
       `GET', the user agent starts with the action URI and appends a `?'
       and the form data set, in `application/x-www-form-urlencoded' format
       as above. The user agent then traverses the link to this URI just as
       if it were an anchor (see 7.2, "Activation of Hyperlinks").

          NOTE - The URL encoding may result in very long URIs, which cause
          some historical HTTP server implementations to exhibit defective
          behavior. As a result, some HTML forms are written using
          `METHOD=POST' even though the form submission has no side-effects.

    8.2.3. Forms with Side-Effects: METHOD=POST

       If the service associated with the processing of a form has side
       effects (for example, modification of a database or subscription to a
       service), the method should be `POST'.

       To process a form whose action URL is an HTTP URL and whose method is
       `POST', the user agent conducts an HTTP POST transaction using the
       action URI, and a message body of type `application/x-www-form-
       urlencoded' format as above. The user agent should display the
       response from the HTTP POST interaction just as it would display the
       response from an HTTP GET above.

    8.2.4. Example Form Submission: Questionnaire Form

       Consider the following document:

        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <title>Sample of HTML Form Submission</title>
        <H1>Sample Questionnaire</H1>
        <P>Please fill out this questionnaire:
        <FORM METHOD="POST" ACTION="http://www.w3.org/sample">
        <P>Your name: <INPUT NAME="name" size="48">
        <P>Male <INPUT NAME="gender" TYPE=RADIO VALUE="male">
        <P>Female <INPUT NAME="gender" TYPE=RADIO VALUE="female">
        <P>Number in family: <INPUT NAME="family" TYPE=text>
        <P>Cities in which you maintain a residence:
        <UL>
        <LI>Kent <INPUT NAME="city" TYPE=checkbox VALUE="kent">
        <LI>Miami <INPUT NAME="city" TYPE=checkbox VALUE="miami">
        <LI>Other <TEXTAREA NAME="other" cols=48 rows=4></textarea>
        </UL>
        Nickname: <INPUT NAME="nickname" SIZE="42">
        <P>Thank you for responding to this questionnaire.
        <P><INPUT TYPE=SUBMIT> <INPUT TYPE=RESET>
        </FORM>

    Berners-Lee & Connolly      Standards Track                    [Page 47]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        The initial state of the form data set is:

        name
                ""

        gender
                "male"

        family
                ""

        other
                ""

        nickname
                ""

        Note that the radio input has an initial value, while the
        checkbox has none.

        The user might edit the fields and request that the form be
        submitted. At that point, suppose the values are:

        name
                "John Doe"

        gender
                "male"

        family
                "5"

        city
                "kent"

        city
                "miami"

        other
                "abc\ndefk"

        nickname
                "J&D"

       The user agent then conducts an HTTP POST transaction using the URI
       `http://www.w3.org/sample'. The message body would be (ignore the
       line break):

    Berners-Lee & Connolly      Standards Track                    [Page 48]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

       name=John+Doe&gender=male&family=5&city=kent&city=miami&
       other=abc%0D%0Adef&nickname=J%26D

    9. HTML Public Text

    9.1. HTML DTD

       This is the Document Type Definition for the HyperText Markup
       Language, level 2.

    <!--    html.dtd

            Document Type Definition for the HyperText Markup Language
                     (HTML DTD)

            $Id: html.dtd,v 1.30 1995/09/21 23:30:19 connolly Exp $

            Author: Daniel W. Connolly <connolly@w3.org>
            See Also: html.decl, html-1.dtd
              http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
    -->

    <!ENTITY % HTML.Version
            "-//IETF//DTD HTML 2.0//EN"

            -- Typical usage:

                <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
                <html>
                ...
                </html>
            --
            >

    <!--============ Feature Test Entities ========================-->

    <!ENTITY % HTML.Recommended "IGNORE"
            -- Certain features of the language are necessary for
               compatibility with widespread usage, but they may
               compromise the structural integrity of a document.
               This feature test entity enables a more prescriptive
               document type definition that eliminates
               those features.
            -->

    <![ %HTML.Recommended [
            <!ENTITY % HTML.Deprecated "IGNORE">

    Berners-Lee & Connolly      Standards Track                    [Page 49]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    ]]>

    <!ENTITY % HTML.Deprecated "INCLUDE"
            -- Certain features of the language are necessary for
               compatibility with earlier versions of the specification,
               but they tend to be used and implemented inconsistently,
               and their use is deprecated. This feature test entity
               enables a document type definition that eliminates
               these features.
            -->

    <!ENTITY % HTML.Highlighting "INCLUDE"
            -- Use this feature test entity to validate that a
               document uses no highlighting tags, which may be
               ignored on minimal implementations.
            -->

    <!ENTITY % HTML.Forms "INCLUDE"
            -- Use this feature test entity to validate that a document
               contains no forms, which may not be supported in minimal
               implementations
            -->

    <!--============== Imported Names ==============================-->

    <!ENTITY % Content-Type "CDATA"
            -- meaning an internet media type
               (aka MIME content type, as per RFC1521)
            -->

    <!ENTITY % HTTP-Method "GET | POST"
            -- as per HTTP specification, in progress
            -->

    <!--========= DTD "Macros" =====================-->

    <!ENTITY % heading "H1|H2|H3|H4|H5|H6">

    <!ENTITY % list " UL | OL | DIR | MENU " >

    <!--======= Character mnemonic entities =================-->

    <!ENTITY % ISOlat1 PUBLIC
      "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML">
    %ISOlat1;

    <!ENTITY amp CDATA "&#38;"     -- ampersand          -->

    Berners-Lee & Connolly      Standards Track                    [Page 50]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!ENTITY gt CDATA "&#62;"      -- greater than       -->
    <!ENTITY lt CDATA "&#60;"      -- less than          -->
    <!ENTITY quot CDATA "&#34;"    -- double quote       -->

    <!--========= SGML Document Access (SDA) Parameter Entities =====-->

    <!-- HTML 2.0 contains SGML Document Access (SDA) fixed attributes
    in support of easy transformation to the International Committee
    for Accessible Document Design (ICADD) DTD
             "-//EC-USA-CDA/ICADD//DTD ICADD22//EN".
    ICADD applications are designed to support usable access to
    structured information by print-impaired individuals through
    Braille, large print and voice synthesis.  For more information on
    SDA & ICADD:
            - ISO 12083:1993, Annex A.8, Facilities for Braille,
              large print and computer voice
            - ICADD ListServ
              <ICADD%ASUACAD.BITNET@ARIZVM1.ccit.arizona.edu>
            - Usenet news group bit.listserv.easi
            - Recording for the Blind, +1 800 221 4792
    -->

    <!ENTITY % SDAFORM  "SDAFORM  CDATA  #FIXED"
              -- one to one mapping        -->
    <!ENTITY % SDARULE  "SDARULE  CDATA  #FIXED"
              -- context-sensitive mapping -->
    <!ENTITY % SDAPREF  "SDAPREF  CDATA  #FIXED"
              -- generated text prefix     -->
    <!ENTITY % SDASUFF  "SDASUFF  CDATA  #FIXED"
              -- generated text suffix     -->
    <!ENTITY % SDASUSP  "SDASUSP  NAME   #FIXED"
              -- suspend transform process -->

    <!--========== Text Markup =====================-->

    <![ %HTML.Highlighting [

    <!ENTITY % font " TT | B | I ">

    <!ENTITY % phrase "EM | STRONG | CODE | SAMP | KBD | VAR | CITE ">

    <!ENTITY % text "#PCDATA | A | IMG | BR | %phrase | %font">

    <!ELEMENT (%font;|%phrase) - - (%text)*>
    <!ATTLIST ( TT | CODE | SAMP | KBD | VAR )
            %SDAFORM; "Lit"

    Berners-Lee & Connolly      Standards Track                    [Page 51]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            >
    <!ATTLIST ( B | STRONG )
            %SDAFORM; "B"
            >
    <!ATTLIST ( I | EM | CITE )
            %SDAFORM; "It"
            >

    <!-- <TT>       Typewriter text                         -->
    <!-- <B>        Bold text                               -->
    <!-- <I>        Italic text                             -->

    <!-- <EM>       Emphasized phrase                       -->
    <!-- <STRONG>   Strong emphasis                         -->
    <!-- <CODE>     Source code phrase                      -->
    <!-- <SAMP>     Sample text or characters               -->
    <!-- <KBD>      Keyboard phrase, e.g. user input        -->
    <!-- <VAR>      Variable phrase or substitutable        -->
    <!-- <CITE>     Name or title of cited work             -->

    <!ENTITY % pre.content "#PCDATA | A | HR | BR | %font | %phrase">

    ]]>

    <!ENTITY % text "#PCDATA | A | IMG | BR">

    <!ELEMENT BR    - O EMPTY>
    <!ATTLIST BR
            %SDAPREF; "&#RE;"
            >

    <!-- <BR>       Line break      -->

    <!--========= Link Markup ======================-->

    <!ENTITY % linkType "NAMES">

    <!ENTITY % linkExtraAttributes
            "REL %linkType #IMPLIED
            REV %linkType #IMPLIED
            URN CDATA #IMPLIED
            TITLE CDATA #IMPLIED
            METHODS NAMES #IMPLIED
            ">

    <![ %HTML.Recommended [
            <!ENTITY % A.content   "(%text)*"

    Berners-Lee & Connolly      Standards Track                    [Page 52]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            -- <H1><a name="xxx">Heading</a></H1>
                    is preferred to
               <a name="xxx"><H1>Heading</H1></a>
            -->
    ]]>

    <!ENTITY % A.content   "(%heading|%text)*">

    <!ELEMENT A     - - %A.content -(A)>
    <!ATTLIST A
            HREF CDATA #IMPLIED
            NAME CDATA #IMPLIED
            %linkExtraAttributes;
            %SDAPREF; "<Anchor: #AttList>"
            >
    <!-- <A>                Anchor; source/destination of link      -->
    <!-- <A NAME="...">     Name of this anchor                     -->
    <!-- <A HREF="...">     Address of link destination             -->
    <!-- <A URN="...">      Permanent address of destination        -->
    <!-- <A REL=...>        Relationship to destination             -->
    <!-- <A REV=...>        Relationship of destination to this     -->
    <!-- <A TITLE="...">    Title of destination (advisory)         -->
    <!-- <A METHODS="...">  Operations on destination (advisory)    -->

    <!--========== Images ==========================-->

    <!ELEMENT IMG    - O EMPTY>
    <!ATTLIST IMG
            SRC CDATA  #REQUIRED
            ALT CDATA #IMPLIED
            ALIGN (top|middle|bottom) #IMPLIED
            ISMAP (ISMAP) #IMPLIED
            %SDAPREF; "<Fig><?SDATrans Img: #AttList>#AttVal(Alt)</Fig>"
            >

    <!-- <IMG>              Image; icon, glyph or illustration      -->
    <!-- <IMG SRC="...">    Address of image object                 -->
    <!-- <IMG ALT="...">    Textual alternative                     -->
    <!-- <IMG ALIGN=...>    Position relative to text               -->
    <!-- <IMG ISMAP>        Each pixel can be a link                -->

    <!--========== Paragraphs=======================-->

    <!ELEMENT P     - O (%text)*>
    <!ATTLIST P
            %SDAFORM; "Para"
            >

    Berners-Lee & Connolly      Standards Track                    [Page 53]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!-- <P>        Paragraph       -->

    <!--========== Headings, Titles, Sections ===============-->

    <!ELEMENT HR    - O EMPTY>
    <!ATTLIST HR
            %SDAPREF; "&#RE;&#RE;"
            >

    <!-- <HR>       Horizontal rule -->

    <!ELEMENT ( %heading )  - -  (%text;)*>
    <!ATTLIST H1
            %SDAFORM; "H1"
            >
    <!ATTLIST H2
            %SDAFORM; "H2"
            >
    <!ATTLIST H3
            %SDAFORM; "H3"
            >
    <!ATTLIST H4
            %SDAFORM; "H4"
            >
    <!ATTLIST H5
            %SDAFORM; "H5"
            >
    <!ATTLIST H6
            %SDAFORM; "H6"
            >

    <!-- <H1>       Heading, level 1 -->
    <!-- <H2>       Heading, level 2 -->
    <!-- <H3>       Heading, level 3 -->
    <!-- <H4>       Heading, level 4 -->
    <!-- <H5>       Heading, level 5 -->
    <!-- <H6>       Heading, level 6 -->

    <!--========== Text Flows ======================-->

    <![ %HTML.Forms [
            <!ENTITY % block.forms "BLOCKQUOTE | FORM | ISINDEX">
    ]]>

    <!ENTITY % block.forms "BLOCKQUOTE">

    Berners-Lee & Connolly      Standards Track                    [Page 54]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <![ %HTML.Deprecated [
            <!ENTITY % preformatted "PRE | XMP | LISTING">
    ]]>

    <!ENTITY % preformatted "PRE">

    <!ENTITY % block "P | %list | DL
            | %preformatted
            | %block.forms">

    <!ENTITY % flow "(%text|%block)*">

    <!ENTITY % pre.content "#PCDATA | A | HR | BR">
    <!ELEMENT PRE - - (%pre.content)*>
    <!ATTLIST PRE
            WIDTH NUMBER #implied
            %SDAFORM; "Lit"
            >

    <!-- <PRE>              Preformatted text               -->
    <!-- <PRE WIDTH=...>    Maximum characters per line     -->

    <![ %HTML.Deprecated [

    <!ENTITY % literal "CDATA"
            -- historical, non-conforming parsing mode where
               the only markup signal is the end tag
               in full
            -->

    <!ELEMENT (XMP|LISTING) - -  %literal>
    <!ATTLIST XMP
            %SDAFORM; "Lit"
            %SDAPREF; "Example:&#RE;"
            >
    <!ATTLIST LISTING
            %SDAFORM; "Lit"
            %SDAPREF; "Listing:&#RE;"
            >

    <!-- <XMP>              Example section         -->
    <!-- <LISTING>          Computer listing        -->

    <!ELEMENT PLAINTEXT - O %literal>
    <!-- <PLAINTEXT>        Plain text passage      -->

    <!ATTLIST PLAINTEXT
            %SDAFORM; "Lit"

    Berners-Lee & Connolly      Standards Track                    [Page 55]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            >
    ]]>

    <!--========== Lists ==================-->

    <!ELEMENT DL    - -  (DT | DD)+>
    <!ATTLIST DL
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            %SDAPREF; "Definition List:"
            >

    <!ELEMENT DT    - O (%text)*>
    <!ATTLIST DT
            %SDAFORM; "Term"
            >

    <!ELEMENT DD    - O %flow>
    <!ATTLIST DD
            %SDAFORM; "LItem"
            >

    <!-- <DL>               Definition list, or glossary    -->
    <!-- <DL COMPACT>       Compact style list              -->
    <!-- <DT>               Term in definition list         -->
    <!-- <DD>               Definition of term              -->

    <!ELEMENT (OL|UL) - -  (LI)+>
    <!ATTLIST OL
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            >
    <!ATTLIST UL
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            >
    <!-- <UL>               Unordered list                  -->
    <!-- <UL COMPACT>       Compact list style              -->
    <!-- <OL>               Ordered, or numbered list       -->
    <!-- <OL COMPACT>       Compact list style              -->

    <!ELEMENT (DIR|MENU) - -  (LI)+ -(%block)>
    <!ATTLIST DIR
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            %SDAPREF; "<LHead>Directory</LHead>"
            >

    Berners-Lee & Connolly      Standards Track                    [Page 56]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!ATTLIST MENU
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            %SDAPREF; "<LHead>Menu</LHead>"
            >

    <!-- <DIR>              Directory list                  -->
    <!-- <DIR COMPACT>      Compact list style              -->
    <!-- <MENU>             Menu list                       -->
    <!-- <MENU COMPACT>     Compact list style              -->

    <!ELEMENT LI    - O %flow>
    <!ATTLIST LI
            %SDAFORM; "LItem"
            >

    <!-- <LI>               List item                       -->

    <!--========== Document Body ===================-->

    <![ %HTML.Recommended [
            <!ENTITY % body.content "(%heading|%block|HR|ADDRESS|IMG)*"
            -- <h1>Heading</h1>
               <p>Text ...
                    is preferred to
               <h1>Heading</h1>
               Text ...
            -->
    ]]>

    <!ENTITY % body.content "(%heading | %text | %block |
                                     HR | ADDRESS)*">

    <!ELEMENT BODY O O  %body.content>

    <!-- <BODY>     Document body   -->

    <!ELEMENT BLOCKQUOTE - - %body.content>
    <!ATTLIST BLOCKQUOTE
            %SDAFORM; "BQ"
            >

    <!-- <BLOCKQUOTE>       Quoted passage  -->

    <!ELEMENT ADDRESS - - (%text|P)*>
    <!ATTLIST  ADDRESS
            %SDAFORM; "Lit"
            %SDAPREF; "Address:&#RE;"

    Berners-Lee & Connolly      Standards Track                    [Page 57]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            >

    <!-- <ADDRESS>  Address, signature, or byline   -->

    <!--======= Forms ====================-->

    <![ %HTML.Forms [

    <!ELEMENT FORM - - %body.content -(FORM) +(INPUT|SELECT|TEXTAREA)>
    <!ATTLIST FORM
            ACTION CDATA #IMPLIED
            METHOD (%HTTP-Method) GET
            ENCTYPE %Content-Type; "application/x-www-form-urlencoded"
            %SDAPREF; "<Para>Form:</Para>"
            %SDASUFF; "<Para>Form End.</Para>"
            >

    <!-- <FORM>                     Fill-out or data-entry form     -->
    <!-- <FORM ACTION="...">        Address for completed form      -->
    <!-- <FORM METHOD=...>          Method of submitting form       -->
    <!-- <FORM ENCTYPE="...">       Representation of form data     -->

    <!ENTITY % InputType "(TEXT | PASSWORD | CHECKBOX |
                            RADIO | SUBMIT | RESET |
                            IMAGE | HIDDEN )">
    <!ELEMENT INPUT - O EMPTY>
    <!ATTLIST INPUT
            TYPE %InputType TEXT
            NAME CDATA #IMPLIED
            VALUE CDATA #IMPLIED
            SRC CDATA #IMPLIED
            CHECKED (CHECKED) #IMPLIED
            SIZE CDATA #IMPLIED
            MAXLENGTH NUMBER #IMPLIED
            ALIGN (top|middle|bottom) #IMPLIED
            %SDAPREF; "Input: "
            >

    <!-- <INPUT>                    Form input datum                -->
    <!-- <INPUT TYPE=...>           Type of input interaction       -->
    <!-- <INPUT NAME=...>           Name of form datum              -->
    <!-- <INPUT VALUE="...">        Default/initial/selected value  -->
    <!-- <INPUT SRC="...">          Address of image                -->
    <!-- <INPUT CHECKED>            Initial state is "on"           -->
    <!-- <INPUT SIZE=...>           Field size hint                 -->
    <!-- <INPUT MAXLENGTH=...>      Data length maximum             -->
    <!-- <INPUT ALIGN=...>          Image alignment                 -->

    Berners-Lee & Connolly      Standards Track                    [Page 58]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!ELEMENT SELECT - - (OPTION+) -(INPUT|SELECT|TEXTAREA)>
    <!ATTLIST SELECT
            NAME CDATA #REQUIRED
            SIZE NUMBER #IMPLIED
            MULTIPLE (MULTIPLE) #IMPLIED
            %SDAFORM; "List"
            %SDAPREF;
            "<LHead>Select #AttVal(Multiple)</LHead>"
            >

    <!-- <SELECT>                   Selection of option(s)          -->
    <!-- <SELECT NAME=...>          Name of form datum              -->
    <!-- <SELECT SIZE=...>          Options displayed at a time     -->
    <!-- <SELECT MULTIPLE>          Multiple selections allowed     -->

    <!ELEMENT OPTION - O (#PCDATA)*>
    <!ATTLIST OPTION
            SELECTED (SELECTED) #IMPLIED
            VALUE CDATA #IMPLIED
            %SDAFORM; "LItem"
            %SDAPREF;
            "Option: #AttVal(Value) #AttVal(Selected)"
            >

    <!-- <OPTION>                   A selection option              -->
    <!-- <OPTION SELECTED>          Initial state                   -->
    <!-- <OPTION VALUE="...">       Form datum value for this option-->

    <!ELEMENT TEXTAREA - - (#PCDATA)* -(INPUT|SELECT|TEXTAREA)>
    <!ATTLIST TEXTAREA
            NAME CDATA #REQUIRED
            ROWS NUMBER #REQUIRED
            COLS NUMBER #REQUIRED
            %SDAFORM; "Para"
            %SDAPREF; "Input Text -- #AttVal(Name): "
            >

    <!-- <TEXTAREA>                 An area for text input          -->
    <!-- <TEXTAREA NAME=...>        Name of form datum              -->
    <!-- <TEXTAREA ROWS=...>        Height of area                  -->
    <!-- <TEXTAREA COLS=...>        Width of area                   -->

    ]]>

    <!--======= Document Head ======================-->

    <![ %HTML.Recommended [

    Berners-Lee & Connolly      Standards Track                    [Page 59]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            <!ENTITY % head.extra "">
    ]]>
    <!ENTITY % head.extra "& NEXTID?">

    <!ENTITY % head.content "TITLE & ISINDEX? & BASE? %head.extra">

    <!ELEMENT HEAD O O  (%head.content) +(META|LINK)>

    <!-- <HEAD>     Document head   -->

    <!ELEMENT TITLE - -  (#PCDATA)*  -(META|LINK)>
    <!ATTLIST TITLE
            %SDAFORM; "Ti"    >

    <!-- <TITLE>    Title of document -->

    <!ELEMENT LINK - O EMPTY>
    <!ATTLIST LINK
            HREF CDATA #REQUIRED
            %linkExtraAttributes;
            %SDAPREF; "Linked to : #AttVal (TITLE) (URN) (HREF)>"    >

    <!-- <LINK>             Link from this document                 -->
    <!-- <LINK HREF="...">  Address of link destination             -->
    <!-- <LINK URN="...">   Lasting name of destination             -->
    <!-- <LINK REL=...>     Relationship to destination             -->
    <!-- <LINK REV=...>     Relationship of destination to this     -->
    <!-- <LINK TITLE="..."> Title of destination (advisory)         -->
    <!-- <LINK METHODS="..."> Operations allowed (advisory)         -->

    <!ELEMENT ISINDEX - O EMPTY>
    <!ATTLIST ISINDEX
            %SDAPREF;
       "<Para>[Document is indexed/searchable.]</Para>">

    <!-- <ISINDEX>          Document is a searchable index          -->

    <!ELEMENT BASE - O EMPTY>
    <!ATTLIST BASE
            HREF CDATA #REQUIRED     >

    <!-- <BASE>             Base context document                   -->
    <!-- <BASE HREF="...">  Address for this document               -->

    <!ELEMENT NEXTID - O EMPTY>
    <!ATTLIST NEXTID
            N CDATA #REQUIRED     >

    Berners-Lee & Connolly      Standards Track                    [Page 60]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!-- <NEXTID>           Next ID to use for link name            -->
    <!-- <NEXTID N=...>     Next ID to use for link name            -->

    <!ELEMENT META - O EMPTY>
    <!ATTLIST META
            HTTP-EQUIV  NAME    #IMPLIED
            NAME        NAME    #IMPLIED
            CONTENT     CDATA   #REQUIRED    >

    <!-- <META>                     Generic Meta-information        -->
    <!-- <META HTTP-EQUIV=...>      HTTP response header name       -->
    <!-- <META NAME=...>            Meta-information name           -->
    <!-- <META CONTENT="...">       Associated information          -->

    <!--======= Document Structure =================-->

    <![ %HTML.Deprecated [
            <!ENTITY % html.content "HEAD, BODY, PLAINTEXT?">
    ]]>
    <!ENTITY % html.content "HEAD, BODY">

    <!ELEMENT HTML O O  (%html.content)>
    <!ENTITY % version.attr "VERSION CDATA #FIXED '%HTML.Version;'">

    <!ATTLIST HTML
            %version.attr;
            %SDAFORM; "Book"
            >

    <!-- <HTML>                     HTML Document   -->

    9.2. Strict HTML DTD

       This document type declaration refers to the HTML DTD with the
       `HTML.Recommended' entity defined as `INCLUDE' rather than IGNORE;
       that is, it refers to the more structurally rigid definition of HTML.

    <!--    html-s.dtd

            Document Type Definition for the HyperText Markup Language
            with strict validation (HTML Strict DTD).

            $Id: html-s.dtd,v 1.3 1995/06/02 18:55:46 connolly Exp $

            Author: Daniel W. Connolly <connolly@w3.org>
            See Also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
    -->

    Berners-Lee & Connolly      Standards Track                    [Page 61]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    <!ENTITY % HTML.Version
            "-//IETF//DTD HTML 2.0 Strict//EN"

            -- Typical usage:

                <!DOCTYPE HTML PUBLIC
                    "-//IETF//DTD HTML Strict//EN">
                <html>
                ...
                </html>
            --
            >

    <!-- Feature Test Entities -->
    <!ENTITY % HTML.Recommended "INCLUDE">

    <!ENTITY % html PUBLIC "-//IETF//DTD HTML 2.0//EN">
    %html;

    9.3. Level 1 HTML DTD

       This document type declaration refers to the HTML DTD with the
       `HTML.Forms' entity defined as `IGNORE' rather than `INCLUDE'.
       Documents which contain <FORM> elements do not conform to this DTD,
       and must use the level 2 DTD.

    <!--    html-1.dtd

            Document Type Definition for the HyperText Markup Language
            with Level 1 Extensions (HTML Level 1 DTD).

            $Id: html-1.dtd,v 1.2 1995/03/29 18:53:10 connolly Exp $

            Author: Daniel W. Connolly <connolly@w3.org>
            See Also: http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html

    -->

    <!ENTITY % HTML.Version
            "-//IETF//DTD HTML 2.0 Level 1//EN"

            -- Typical usage:

                <!DOCTYPE HTML PUBLIC
                    "-//IETF//DTD HTML Level 1//EN">
                <html>
                ...
                </html>

    Berners-Lee & Connolly      Standards Track                    [Page 62]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

            --
            >

    <!-- Feature Test Entities -->
    <!ENTITY % HTML.Forms "IGNORE">

    <!ENTITY % html PUBLIC "-//IETF//DTD HTML 2.0//EN">
    %html;

    9.4. Strict Level 1 HTML DTD

       This document type declaration refers to the level 1 HTML DTD with
       the `HTML.Recommended' entity defined as `INCLUDE' rather than
       IGNORE; that is, it refers to the more structurally rigid definition
       of HTML.

    <!--    html-1s.dtd

            Document Type Definition for the HyperText Markup Language
            Struct Level 1

            $Id: html-1s.dtd,v 1.3 1995/06/02 18:55:43 connolly Exp $

            Author: Daniel W. Connolly <connolly@w3.org>
            See Also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
    -->

    <!ENTITY % HTML.Version
            "-//IETF//DTD HTML 2.0 Strict Level 1//EN"

            -- Typical usage:

                <!DOCTYPE HTML PUBLIC
                    "-//IETF//DTD HTML Strict Level 1//EN">
                <html>
                ...
                </html>
            --
            >

    <!-- Feature Test Entities -->

    <!ENTITY % HTML.Recommended "INCLUDE">

    <!ENTITY % html-1 PUBLIC "-//IETF//DTD HTML 2.0 Level 1//EN">
    %html-1;

    Berners-Lee & Connolly      Standards Track                    [Page 63]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    9.5. SGML Declaration for HTML

       This is the SGML Declaration for HyperText Markup Language.

    <!SGML  "ISO 8879:1986"
    --
            SGML Declaration for HyperText Markup Language (HTML).

    --

    CHARSET
             BASESET  "ISO 646:1983//CHARSET
                       International Reference Version
                       (IRV)//ESC 2/5 4/0"
             DESCSET  0   9   UNUSED
                      9   2   9
                      11  2   UNUSED
                      13  1   13
                      14  18  UNUSED
                      32  95  32
                      127 1   UNUSED
         BASESET   "ISO Registration Number 100//CHARSET
                    ECMA-94 Right Part of
                    Latin Alphabet Nr. 1//ESC 2/13 4/1"

             DESCSET  128  32   UNUSED
                      160  96    32

    CAPACITY        SGMLREF
                    TOTALCAP        150000
                    GRPCAP          150000
                    ENTCAP          150000

    SCOPE    DOCUMENT
    SYNTAX
             SHUNCHAR CONTROLS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
                     17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 127
             BASESET  "ISO 646:1983//CHARSET
                       International Reference Version
                       (IRV)//ESC 2/5 4/0"
             DESCSET  0 128 0
             FUNCTION
                      RE          13
                      RS          10
                      SPACE       32
                      TAB SEPCHAR  9
             NAMING   LCNMSTRT ""
                      UCNMSTRT ""

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

                      LCNMCHAR ".-"
                      UCNMCHAR ".-"
                      NAMECASE GENERAL YES
                               ENTITY  NO
             DELIM    GENERAL  SGMLREF
                      SHORTREF SGMLREF
             NAMES    SGMLREF
             QUANTITY SGMLREF
                      ATTSPLEN 2100
                      LITLEN   1024
                      NAMELEN  72    -- somewhat arbitrary; taken from
                                    internet line length conventions --
                      PILEN    1024
                      TAGLVL   100
                      TAGLEN   2100
                      GRPGTCNT 150
                      GRPCNT   64

    FEATURES
      MINIMIZE
        DATATAG  NO
        OMITTAG  YES
        RANK     NO
        SHORTTAG YES
      LINK
        SIMPLE   NO
        IMPLICIT NO
        EXPLICIT NO
      OTHER
        CONCUR   NO
        SUBDOC   NO
        FORMAL   YES
      APPINFO    "SDA"  -- conforming SGML Document Access application
                        --
    >
    <!--
            $Id: html.decl,v 1.17 1995/06/08 14:59:32 connolly Exp $

            Author: Daniel W. Connolly <connolly@w3.org>

            See also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
     -->

    9.6. Sample SGML Open Entity Catalog for HTML

       The SGML standard describes an "entity manager" as the portion or
       component of an SGML system that maps SGML entities into the actual
       storage model (e.g., the file system). The standard itself does not

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       define a particular mapping methodology or notation.

       To assist the interoperability among various SGML tools and systems,
       the SGML Open consortium has passed a technical resolution that
       defines a format for an application-independent entity catalog that
       maps external identifiers and/or entity names to file names.

       Each entry in the catalog associates a storage object identifier
       (such as a file name) with information about the external entity that
       appears in the SGML document. In addition to entries that associate
       public identifiers, a catalog entry can associate an entity name with
       a storage object identifier. For example, the following are possible
       catalog entries:

            -- catalog: SGML Open style entity catalog for HTML --
            -- $Id: catalog,v 1.3 1995/09/21 23:30:23 connolly Exp $ --

            -- Ways to refer to Level 2: most general to most specific --
    PUBLIC  "-//IETF//DTD HTML//EN"                 html.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0//EN"             html.dtd
    PUBLIC  "-//IETF//DTD HTML Level 2//EN"         html.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0 Level 2//EN"     html.dtd

            -- Ways to refer to Level 1: most general to most specific --
    PUBLIC  "-//IETF//DTD HTML Level 1//EN"         html-1.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0 Level 1//EN"     html-1.dtd

            -- Ways to refer to
                     Strict Level 2: most general to most specific --
    PUBLIC  "-//IETF//DTD HTML Strict//EN"                  html-s.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0 Strict//EN"              html-s.dtd
    PUBLIC  "-//IETF//DTD HTML Strict Level 2//EN"          html-s.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 2//EN"      html-s.dtd

            -- Ways to refer to
                     Strict Level 1: most general to most specific --
    PUBLIC  "-//IETF//DTD HTML Strict Level 1//EN"          html-1s.dtd
    PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 1//EN"      html-1s.dtd

            -- ISO latin 1 entity set for HTML --
    PUBLIC  "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML" ISOlat1\
    sgml

    9.7. Character Entity Sets

       The HTML DTD defines the following entities. They represent
       particular graphic characters which have special meanings in places
       in the markup, or may not be part of the character set available to

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

       the writer.

    9.7.1. Numeric and Special Graphic Entity Set

       The following table lists each of the characters included from the
       Numeric and Special Graphic entity set, along with its name, syntax
       for use, and description. This list is derived from `ISO Standard
       8879:1986//ENTITIES Numeric and Special Graphic//EN'.  However, HTML
       does not include for the entire entity set -- only the entities
       listed below are included.

        GLYPH   NAME    SYNTAX  DESCRIPTION
        <       lt      &lt;    Less than sign
        >       gt      &gt;    Greater than signn
        &       amp     &amp;   Ampersand
        "       quot    &quot;  Double quote sign

    9.7.2. ISO Latin 1 Character Entity Set

       The following public text lists each of the characters specified in
       the Added Latin 1 entity set, along with its name, syntax for use,
       and description. This list is derived from ISO Standard
       8879:1986//ENTITIES Added Latin 1//EN. HTML includes the entire
       entity set.

    <!-- (C) International Organization for Standardization 1986
         Permission to copy in any form is granted for use with
         conforming SGML systems and applications as defined in
         ISO 8879, provided this notice is included in all copies.
    -->
    <!-- Character entity set. Typical invocation:
         <!ENTITY % ISOlat1 PUBLIC
           "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML">
         %ISOlat1;
    -->
    <!--    Modified for use in HTML
            $Id: ISOlat1.sgml,v 1.2 1994/11/30 23:45:12 connolly Exp $ -->
    <!ENTITY AElig  CDATA "&#198;" -- capital AE diphthong (ligature) -->
    <!ENTITY Aacute CDATA "&#193;" -- capital A, acute accent -->
    <!ENTITY Acirc  CDATA "&#194;" -- capital A, circumflex accent -->
    <!ENTITY Agrave CDATA "&#192;" -- capital A, grave accent -->
    <!ENTITY Aring  CDATA "&#197;" -- capital A, ring -->
    <!ENTITY Atilde CDATA "&#195;" -- capital A, tilde -->
    <!ENTITY Auml   CDATA "&#196;" -- capital A, dieresis or umlaut mark -->
    <!ENTITY Ccedil CDATA "&#199;" -- capital C, cedilla -->
    <!ENTITY ETH    CDATA "&#208;" -- capital Eth, Icelandic -->
    <!ENTITY Eacute CDATA "&#201;" -- capital E, acute accent -->
    <!ENTITY Ecirc  CDATA "&#202;" -- capital E, circumflex accent -->

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    <!ENTITY Egrave CDATA "&#200;" -- capital E, grave accent -->
    <!ENTITY Euml   CDATA "&#203;" -- capital E, dieresis or umlaut mark -->
    <!ENTITY Iacute CDATA "&#205;" -- capital I, acute accent -->
    <!ENTITY Icirc  CDATA "&#206;" -- capital I, circumflex accent -->
    <!ENTITY Igrave CDATA "&#204;" -- capital I, grave accent -->
    <!ENTITY Iuml   CDATA "&#207;" -- capital I, dieresis or umlaut mark -->
    <!ENTITY Ntilde CDATA "&#209;" -- capital N, tilde -->
    <!ENTITY Oacute CDATA "&#211;" -- capital O, acute accent -->
    <!ENTITY Ocirc  CDATA "&#212;" -- capital O, circumflex accent -->
    <!ENTITY Ograve CDATA "&#210;" -- capital O, grave accent -->
    <!ENTITY Oslash CDATA "&#216;" -- capital O, slash -->
    <!ENTITY Otilde CDATA "&#213;" -- capital O, tilde -->
    <!ENTITY Ouml   CDATA "&#214;" -- capital O, dieresis or umlaut mark -->
    <!ENTITY THORN  CDATA "&#222;" -- capital THORN, Icelandic -->
    <!ENTITY Uacute CDATA "&#218;" -- capital U, acute accent -->
    <!ENTITY Ucirc  CDATA "&#219;" -- capital U, circumflex accent -->
    <!ENTITY Ugrave CDATA "&#217;" -- capital U, grave accent -->
    <!ENTITY Uuml   CDATA "&#220;" -- capital U, dieresis or umlaut mark -->
    <!ENTITY Yacute CDATA "&#221;" -- capital Y, acute accent -->
    <!ENTITY aacute CDATA "&#225;" -- small a, acute accent -->
    <!ENTITY acirc  CDATA "&#226;" -- small a, circumflex accent -->
    <!ENTITY aelig  CDATA "&#230;" -- small ae diphthong (ligature) -->
    <!ENTITY agrave CDATA "&#224;" -- small a, grave accent -->
    <!ENTITY aring  CDATA "&#229;" -- small a, ring -->
    <!ENTITY atilde CDATA "&#227;" -- small a, tilde -->
    <!ENTITY auml   CDATA "&#228;" -- small a, dieresis or umlaut mark -->
    <!ENTITY ccedil CDATA "&#231;" -- small c, cedilla -->
    <!ENTITY eacute CDATA "&#233;" -- small e, acute accent -->
    <!ENTITY ecirc  CDATA "&#234;" -- small e, circumflex accent -->
    <!ENTITY egrave CDATA "&#232;" -- small e, grave accent -->
    <!ENTITY eth    CDATA "&#240;" -- small eth, Icelandic -->
    <!ENTITY euml   CDATA "&#235;" -- small e, dieresis or umlaut mark -->
    <!ENTITY iacute CDATA "&#237;" -- small i, acute accent -->
    <!ENTITY icirc  CDATA "&#238;" -- small i, circumflex accent -->
    <!ENTITY igrave CDATA "&#236;" -- small i, grave accent -->
    <!ENTITY iuml   CDATA "&#239;" -- small i, dieresis or umlaut mark -->
    <!ENTITY ntilde CDATA "&#241;" -- small n, tilde -->
    <!ENTITY oacute CDATA "&#243;" -- small o, acute accent -->
    <!ENTITY ocirc  CDATA "&#244;" -- small o, circumflex accent -->
    <!ENTITY ograve CDATA "&#242;" -- small o, grave accent -->
    <!ENTITY oslash CDATA "&#248;" -- small o, slash -->
    <!ENTITY otilde CDATA "&#245;" -- small o, tilde -->
    <!ENTITY ouml   CDATA "&#246;" -- small o, dieresis or umlaut mark -->
    <!ENTITY szlig  CDATA "&#223;" -- small sharp s, German (sz ligature)->
    <!ENTITY thorn  CDATA "&#254;" -- small thorn, Icelandic -->
    <!ENTITY uacute CDATA "&#250;" -- small u, acute accent -->
    <!ENTITY ucirc  CDATA "&#251;" -- small u, circumflex accent -->
    <!ENTITY ugrave CDATA "&#249;" -- small u, grave accent -->

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    <!ENTITY uuml   CDATA "&#252;" -- small u, dieresis or umlaut mark -->
    <!ENTITY yacute CDATA "&#253;" -- small y, acute accent -->
    <!ENTITY yuml   CDATA "&#255;" -- small y, dieresis or umlaut mark -->

    10. Security Considerations

       Anchors, embedded images, and all other elements which contain URIs
       as parameters may cause the URI to be dereferenced in response to
       user input. In this case, the security considerations of [URL] apply.

       The widely deployed methods for submitting forms requests -- HTTP and
       SMTP -- provide little assurance of confidentiality.  Information
       providers who request sensitive information via forms -- especially
       by way of the `PASSWORD' type input field (see 8.1.2, "Input Field:
       INPUT") -- should be aware and make their users aware of the lack of
       confidentiality.

    11. References

        [URI]
                Berners-Lee, T., "Universal Resource Identifiers in WWW:
                A Unifying Syntax for the Expression of Names and
                Addresses of Objects on the Network as used in the
                World- Wide Web",  RFC 1630, CERN, June 1994.
                <URL:ftp://ds.internic.net/rfc/rfc1630.txt>

        [URL]
                Berners-Lee, T., Masinter, L., and M. McCahill, "Uniform
                Resource Locators (URL)", RFC 1738, CERN, Xerox PARC,
                University of Minnesota, December 1994.
                <URL:ftp://ds.internic.net/rfc/rfc1738.txt>

        [HTTP]
                Berners-Lee, T., Fielding, R., and H. Frystyk Nielsen,
                "Hypertext Transfer Protocol - HTTP/1.0", Work in
                Progress, MIT, UC Irvine, CERN, March 1995.

        [MIME]
                Borenstein, N., and N. Freed. "MIME (Multipurpose
                Internet Mail Extensions) Part One: Mechanisms for
                Specifying and Describing the Format of Internet Message
                Bodies", RFC 1521, Bellcore, Innosoft, September 1993.
                <URL:ftp://ds.internic.net/rfc/rfc1521.txt>

        [RELURL]
                Fielding, R., "Relative Uniform Resource Locators", RFC
                1808, June 1995
                <URL:ftp://ds.internic.net/rfc/rfc1808.txt>

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        [GOLD90]
                Goldfarb, C., "The SGML Handbook", Y. Rubinsky, Ed.,
                Oxford University Press, 1990.

        [DEXTER]
                Frank Halasz and Mayer Schwartz, "The Dexter Hypertext
                Reference Model", Communications of the ACM, pp.
                30-39, vol. 37 no. 2, Feb 1994.

        [IMEDIA]
                Postel, J., "Media Type Registration Procedure",
                RFC 1590, USC/Information Sciences Institute, March 1994.
                <URL:ftp://ds.internic.net/rfc/rfc1590.txt>

        [IANA]
                Reynolds, J., and J. Postel, "Assigned Numbers", STD 2,
                RFC 1700, USC/Information Sciecnes Institute, October
                1994.  <URL:ftp://ds.internic.net/rfc/rfc1700.txt>

        [SQ91]
                SoftQuad. "The SGML Primer", 3rd ed., SoftQuad Inc.,
                1991. <URL:http://www.sq.com/>

        [ISO-646]
                ISO/IEC 646:1991 Information technology -- ISO 7-bit
                coded character set for information interchange
                <URL:http://www.iso.ch/cate/d4777.html>

        [ISO-10646]
                ISO/IEC 10646-1:1993 Information technology -- Universal
                Multiple-Octet Coded Character Set (UCS) -- Part 1:
                Architecture and Basic Multilingual Plane
                <URL:http://www.iso.ch/cate/d18741.html>

        [ISO-8859-1]
                ISO 8859. International Standard -- Information
                Processing -- 8-bit Single-Byte Coded Graphic Character
                Sets -- Part 1: Latin Alphabet No. 1, ISO 8859-1:1987.
                <URL:http://www.iso.ch/cate/d16338.html>

        [SGML]
                ISO 8879. Information Processing -- Text and Office
                Systems - Standard Generalized Markup Language (SGML),
                1986. <URL:http://www.iso.ch/cate/d16387.html>

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    12. Acknowledgments

       The HTML document type was designed by Tim Berners-Lee at CERN as
       part of the 1990 World Wide Web project. In 1992, Dan Connolly wrote
       the HTML Document Type Definition (DTD) and a brief HTML
       specification.

       Since 1993, a wide variety of Internet participants have contributed
       to the evolution of HTML, which has included the addition of in-line
       images introduced by the NCSA Mosaic software for WWW. Dave Raggett
       played an important role in deriving the forms material from the
       HTML+ specification.

       Dan Connolly and Karen Olson Muldrow rewrote the HTML Specification
       in 1994. The document was then edited by the HTML working group as a
       whole, with updates being made by Eric Schieler, Mike Knezovich, and
       Eric W. Sink at Spyglass, Inc.  Finally, Roy Fielding restructured
       the entire draft into its current form.

       Special thanks to the many active participants in the HTML working
       group, too numerous to list individually, without whom there would be
       no standards process and no standard. That this document approaches
       its objective of carefully converging a description of current
       practice and formalization of HTML's relationship to SGML is a
       tribute to their effort.

    12.1. Authors' Addresses

       Tim Berners-Lee
       Director, W3 Consortium
       MIT Laboratory for Computer Science
       545 Technology Square
       Cambridge, MA 02139, U.S.A.

       Phone: +1 (617) 253 9670
       Fax: +1 (617) 258 8682
       EMail: timbl@w3.org

       Daniel W. Connolly
       Research Technical Staff, W3 Consortium
       MIT Laboratory for Computer Science
       545 Technology Square
       Cambridge, MA 02139, U.S.A.

       Phone: +1 (617) 258 8682
       EMail: connolly@w3.org
       URI: http://www.w3.org/hypertext/WWW/People/Connolly/

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

    13. The HTML Coded Character Set

       This list details the code positions and characters of the HTML
       document character set, specified in 9.5, "SGML Declaration for
       HTML". This coded character set is based on [ISO-8859-1].

        REFERENCE       DESCRIPTION
        --------------  -----------
        &#00; - &#08;   Unused
        &#09;           Horizontal tab
        &#10;           Line feed
        &#11; - &#12;   Unused
        &#13;           Carriage Return
        &#14; - &#31;   Unused
        &#32;           Space
        &#33;           Exclamation mark
        &#34;           Quotation mark
        &#35;           Number sign
        &#36;           Dollar sign
        &#37;           Percent sign
        &#38;           Ampersand
        &#39;           Apostrophe
        &#40;           Left parenthesis
        &#41;           Right parenthesis
        &#42;           Asterisk
        &#43;           Plus sign
        &#44;           Comma
        &#45;           Hyphen
        &#46;           Period (fullstop)
        &#47;           Solidus (slash)
        &#48; - &#57;   Digits 0-9
        &#58;           Colon
        &#59;           Semi-colon
        &#60;           Less than
        &#61;           Equals sign
        &#62;           Greater than
        &#63;           Question mark
        &#64;           Commercial at
        &#65; - &#90;   Letters A-Z
        &#91;           Left square bracket
        &#92;           Reverse solidus (backslash)
        &#93;           Right square bracket
        &#94;           Caret
        &#95;           Horizontal bar (underscore)
        &#96;           Acute accent
        &#97; - &#122;  Letters a-z
        &#123;          Left curly brace
        &#124;          Vertical bar

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        &#125;          Right curly brace
        &#126;          Tilde
        &#127; - &#159; Unused
        &#160;          Non-breaking Space
        &#161;          Inverted exclamation
        &#162;          Cent sign
        &#163;          Pound sterling
        &#164;          General currency sign
        &#165;          Yen sign
        &#166;          Broken vertical bar
        &#167;          Section sign
        &#168;          Umlaut (dieresis)
        &#169;          Copyright
        &#170;          Feminine ordinal
        &#171;          Left angle quote, guillemotleft
        &#172;          Not sign
        &#173;          Soft hyphen
        &#174;          Registered trademark
        &#175;          Macron accent
        &#176;          Degree sign
        &#177;          Plus or minus
        &#178;          Superscript two
        &#179;          Superscript three
        &#180;          Acute accent
        &#181;          Micro sign
        &#182;          Paragraph sign
        &#183;          Middle dot
        &#184;          Cedilla
        &#185;          Superscript one
        &#186;          Masculine ordinal
        &#187;          Right angle quote, guillemotright
        &#188;          Fraction one-fourth
        &#189;          Fraction one-half
        &#190;          Fraction three-fourths
        &#191;          Inverted question mark
        &#192;          Capital A, grave accent
        &#193;          Capital A, acute accent
        &#194;          Capital A, circumflex accent
        &#195;          Capital A, tilde
        &#196;          Capital A, dieresis or umlaut mark
        &#197;          Capital A, ring
        &#198;          Capital AE dipthong (ligature)
        &#199;          Capital C, cedilla
        &#200;          Capital E, grave accent
        &#201;          Capital E, acute accent
        &#202;          Capital E, circumflex accent
        &#203;          Capital E, dieresis or umlaut mark
        &#204;          Capital I, grave accent

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        &#205;          Capital I, acute accent
        &#206;          Capital I, circumflex accent
        &#207;          Capital I, dieresis or umlaut mark
        &#208;          Capital Eth, Icelandic
        &#209;          Capital N, tilde
        &#210;          Capital O, grave accent
        &#211;          Capital O, acute accent
        &#212;          Capital O, circumflex accent
        &#213;          Capital O, tilde
        &#214;          Capital O, dieresis or umlaut mark
        &#215;          Multiply sign
        &#216;          Capital O, slash
        &#217;          Capital U, grave accent
        &#218;          Capital U, acute accent
        &#219;          Capital U, circumflex accent
        &#220;          Capital U, dieresis or umlaut mark
        &#221;          Capital Y, acute accent
        &#222;          Capital THORN, Icelandic
        &#223;          Small sharp s, German (sz ligature)
        &#224;          Small a, grave accent
        &#225;          Small a, acute accent
        &#226;          Small a, circumflex accent
        &#227;          Small a, tilde
        &#228;          Small a, dieresis or umlaut mark
        &#229;          Small a, ring
        &#230;          Small ae dipthong (ligature)
        &#231;          Small c, cedilla
        &#232;          Small e, grave accent
        &#233;          Small e, acute accent
        &#234;          Small e, circumflex accent
        &#235;          Small e, dieresis or umlaut mark
        &#236;          Small i, grave accent
        &#237;          Small i, acute accent
        &#238;          Small i, circumflex accent
        &#239;          Small i, dieresis or umlaut mark
        &#240;          Small eth, Icelandic
        &#241;          Small n, tilde
        &#242;          Small o, grave accent
        &#243;          Small o, acute accent
        &#244;          Small o, circumflex accent
        &#245;          Small o, tilde
        &#246;          Small o, dieresis or umlaut mark
        &#247;          Division sign
        &#248;          Small o, slash
        &#249;          Small u, grave accent
        &#250;          Small u, acute accent
        &#251;          Small u, circumflex accent
        &#252;          Small u, dieresis or umlaut mark

    Berners-Lee & Connolly      Standards Track                    [Page 74]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        &#253;          Small y, acute accent
        &#254;          Small thorn, Icelandic
        &#255;          Small y, dieresis or umlaut mark

    14. Proposed Entities

       The HTML DTD references the "Added Latin 1" entity set, which only
       supplies named entities for a subset of the non-ASCII characters in
       [ISO-8859-1], namely the accented characters. The following entities
       should be supported so that all ISO 8859-1 characters may only be
       referenced symbolically. The names for these entities are taken from
       the appendixes of [SGML].

        <!ENTITY nbsp   CDATA "&#160;" -- no-break space -->
        <!ENTITY iexcl  CDATA "&#161;" -- inverted exclamation mark -->
        <!ENTITY cent   CDATA "&#162;" -- cent sign -->
        <!ENTITY pound  CDATA "&#163;" -- pound sterling sign -->
        <!ENTITY curren CDATA "&#164;" -- general currency sign -->
        <!ENTITY yen    CDATA "&#165;" -- yen sign -->
        <!ENTITY brvbar CDATA "&#166;" -- broken (vertical) bar -->
        <!ENTITY sect   CDATA "&#167;" -- section sign -->
        <!ENTITY uml    CDATA "&#168;" -- umlaut (dieresis) -->
        <!ENTITY copy   CDATA "&#169;" -- copyright sign -->
        <!ENTITY ordf   CDATA "&#170;" -- ordinal indicator, feminine -->
        <!ENTITY laquo  CDATA "&#171;" -- angle quotation mark, left -->
        <!ENTITY not    CDATA "&#172;" -- not sign -->
        <!ENTITY shy    CDATA "&#173;" -- soft hyphen -->
        <!ENTITY reg    CDATA "&#174;" -- registered sign -->
        <!ENTITY macr   CDATA "&#175;" -- macron -->
        <!ENTITY deg    CDATA "&#176;" -- degree sign -->
        <!ENTITY plusmn CDATA "&#177;" -- plus-or-minus sign -->
        <!ENTITY sup2   CDATA "&#178;" -- superscript two -->
        <!ENTITY sup3   CDATA "&#179;" -- superscript three -->
        <!ENTITY acute  CDATA "&#180;" -- acute accent -->
        <!ENTITY micro  CDATA "&#181;" -- micro sign -->
        <!ENTITY para   CDATA "&#182;" -- pilcrow (paragraph sign) -->
        <!ENTITY middot CDATA "&#183;" -- middle dot -->
        <!ENTITY cedil  CDATA "&#184;" -- cedilla -->
        <!ENTITY sup1   CDATA "&#185;" -- superscript one -->
        <!ENTITY ordm   CDATA "&#186;" -- ordinal indicator, masculine -->
        <!ENTITY raquo  CDATA "&#187;" -- angle quotation mark, right -->
        <!ENTITY frac14 CDATA "&#188;" -- fraction one-quarter -->
        <!ENTITY frac12 CDATA "&#189;" -- fraction one-half -->
        <!ENTITY frac34 CDATA "&#190;" -- fraction three-quarters -->
        <!ENTITY iquest CDATA "&#191;" -- inverted question mark -->
        <!ENTITY Agrave CDATA "&#192;" -- capital A, grave accent -->
        <!ENTITY Aacute CDATA "&#193;" -- capital A, acute accent -->
        <!ENTITY Acirc  CDATA "&#194;" -- capital A, circumflex accent -->

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    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        <!ENTITY Atilde CDATA "&#195;" -- capital A, tilde -->
        <!ENTITY Auml   CDATA "&#196;" -- capital A, dieresis or umlaut mark -->
        <!ENTITY Aring  CDATA "&#197;" -- capital A, ring -->
        <!ENTITY AElig  CDATA "&#198;" -- capital AE diphthong (ligature) -->
        <!ENTITY Ccedil CDATA "&#199;" -- capital C, cedilla -->
        <!ENTITY Egrave CDATA "&#200;" -- capital E, grave accent -->
        <!ENTITY Eacute CDATA "&#201;" -- capital E, acute accent -->
        <!ENTITY Ecirc  CDATA "&#202;" -- capital E, circumflex accent -->
        <!ENTITY Euml   CDATA "&#203;" -- capital E, dieresis or umlaut mark -->
        <!ENTITY Igrave CDATA "&#204;" -- capital I, grave accent -->
        <!ENTITY Iacute CDATA "&#205;" -- capital I, acute accent -->
        <!ENTITY Icirc  CDATA "&#206;" -- capital I, circumflex accent -->
        <!ENTITY Iuml   CDATA "&#207;" -- capital I, dieresis or umlaut mark -->
        <!ENTITY ETH    CDATA "&#208;" -- capital Eth, Icelandic -->
        <!ENTITY Ntilde CDATA "&#209;" -- capital N, tilde -->
        <!ENTITY Ograve CDATA "&#210;" -- capital O, grave accent -->
        <!ENTITY Oacute CDATA "&#211;" -- capital O, acute accent -->
        <!ENTITY Ocirc  CDATA "&#212;" -- capital O, circumflex accent -->
        <!ENTITY Otilde CDATA "&#213;" -- capital O, tilde -->
        <!ENTITY Ouml   CDATA "&#214;" -- capital O, dieresis or umlaut mark -->
        <!ENTITY times  CDATA "&#215;" -- multiply sign -->
        <!ENTITY Oslash CDATA "&#216;" -- capital O, slash -->
        <!ENTITY Ugrave CDATA "&#217;" -- capital U, grave accent -->
        <!ENTITY Uacute CDATA "&#218;" -- capital U, acute accent -->
        <!ENTITY Ucirc  CDATA "&#219;" -- capital U, circumflex accent -->
        <!ENTITY Uuml   CDATA "&#220;" -- capital U, dieresis or umlaut mark -->
        <!ENTITY Yacute CDATA "&#221;" -- capital Y, acute accent -->
        <!ENTITY THORN  CDATA "&#222;" -- capital THORN, Icelandic -->
        <!ENTITY szlig  CDATA "&#223;" -- small sharp s, German (sz ligature) -->
        <!ENTITY agrave CDATA "&#224;" -- small a, grave accent -->
        <!ENTITY aacute CDATA "&#225;" -- small a, acute accent -->
        <!ENTITY acirc  CDATA "&#226;" -- small a, circumflex accent -->
        <!ENTITY atilde CDATA "&#227;" -- small a, tilde -->
        <!ENTITY auml   CDATA "&#228;" -- small a, dieresis or umlaut mark -->
        <!ENTITY aring  CDATA "&#229;" -- small a, ring -->
        <!ENTITY aelig  CDATA "&#230;" -- small ae diphthong (ligature) -->
        <!ENTITY ccedil CDATA "&#231;" -- small c, cedilla -->
        <!ENTITY egrave CDATA "&#232;" -- small e, grave accent -->
        <!ENTITY eacute CDATA "&#233;" -- small e, acute accent -->
        <!ENTITY ecirc  CDATA "&#234;" -- small e, circumflex accent -->
        <!ENTITY euml   CDATA "&#235;" -- small e, dieresis or umlaut mark -->
        <!ENTITY igrave CDATA "&#236;" -- small i, grave accent -->
        <!ENTITY iacute CDATA "&#237;" -- small i, acute accent -->
        <!ENTITY icirc  CDATA "&#238;" -- small i, circumflex accent -->
        <!ENTITY iuml   CDATA "&#239;" -- small i, dieresis or umlaut mark -->
        <!ENTITY eth    CDATA "&#240;" -- small eth, Icelandic -->
        <!ENTITY ntilde CDATA "&#241;" -- small n, tilde -->
        <!ENTITY ograve CDATA "&#242;" -- small o, grave accent -->

    Berners-Lee & Connolly      Standards Track                    [Page 76]

    RFC 1866            Hypertext Markup Language - 2.0        November 1995

        <!ENTITY oacute CDATA "&#243;" -- small o, acute accent -->
        <!ENTITY ocirc  CDATA "&#244;" -- small o, circumflex accent -->
        <!ENTITY otilde CDATA "&#245;" -- small o, tilde -->
        <!ENTITY ouml   CDATA "&#246;" -- small o, dieresis or umlaut mark -->
        <!ENTITY divide CDATA "&#247;" -- divide sign -->
        <!ENTITY oslash CDATA "&#248;" -- small o, slash -->
        <!ENTITY ugrave CDATA "&#249;" -- small u, grave accent -->
        <!ENTITY uacute CDATA "&#250;" -- small u, acute accent -->
        <!ENTITY ucirc  CDATA "&#251;" -- small u, circumflex accent -->
        <!ENTITY uuml   CDATA "&#252;" -- small u, dieresis or umlaut mark -->
        <!ENTITY yacute CDATA "&#253;" -- small y, acute accent -->
        <!ENTITY thorn  CDATA "&#254;" -- small thorn, Icelandic -->
        <!ENTITY yuml   CDATA "&#255;" -- small y, dieresis or umlaut mark -->

    Berners-Lee & Connolly      Standards Track                    [Page 77]

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