2004/id/draft-ietf-html-spec-05.txt


HTML Working Group                                        T. Berners-Lee
INTERNET-DRAFT                                                   MIT/W3C
<draft-ietf-html-spec-05.txt>                                D. Connolly
Expires: In six months                                    August 8, 1995


                    Hypertext Markup Language - 2.0


Status of this Memo

This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas, and
its working groups. Note that other groups may also distribute working
documents as Internet-Drafts.

Internet-Drafts are draft documents valid for a maximum of six months
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Distribution of this document is unlimited. Please send comments to the
HTML working group (HTML-WG) of the Internet Engineering Task Force
(IETF) at <html-wg@oclc.org>. Discussions of the group are archived at
<URL:http://www.acl.lanl.gov/HTML_WG/archives.html>.


                            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.


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                                CONTENTS


    1      Introduction .......................................... 3
    1.1    Scope ................................................. 3
    1.2    Conformance ........................................... 3
    2      Terms ................................................. 5
    3      HTML as an Application of SGML ........................ 9
    3.1    SGML Documents ........................................ 9
    3.2    HTML Lexical Syntax .................................. 11
    3.3    HTML Public Text Identifiers ......................... 15
    3.4    Example HTML Document ................................ 16
    4      HTML as an Internet Media Type ....................... 16
    4.1    text/html media type ................................. 16
    4.2    HTML Document Representation ......................... 17
    5      Document Structure ................................... 18
    5.1    Document Element: HTML ............................... 19
    5.2    Head: HEAD ........................................... 19
    5.3    Body: BODY ........................................... 22
    5.4    Headings: H1 ... H6 .................................. 22
    5.5    Block Structuring Elements ........................... 23
    5.6    List Elements ........................................ 25
    5.7    Phrase Markup ........................................ 28
    5.8    Line Break: BR ....................................... 31
    5.9    Horizontal Rule: HR .................................. 31
    5.10   Image: IMG ........................................... 31
    6      Characters, Words, and Paragraphs .................... 33
    6.1    The HTML Document Character Set ...................... 33
    7      Hyperlinks ........................................... 34
    7.1    Accessing Resources .................................. 34
    7.2    Activation of Hyperlinks ............................. 35
    7.3    Simultaneous Presentation of Image Resources ......... 35
    7.4    Fragment Identifiers ................................. 36
    7.5    Queries and Indexes .................................. 36
    7.6    Image Maps ........................................... 37
    8      Forms ................................................ 37
    8.1    Form Elements ........................................ 37
    8.2    Form Submission ...................................... 42
    9      HTML Public Text ..................................... 45
    9.1    HTML DTD ............................................. 46
    9.2    Strict HTML DTD ...................................... 57
    9.3    Level 1 HTML DTD ..................................... 57
    9.4    Strict Level 1 HTML DTD .............................. 58
    9.5    SGML Declaration for HTML ............................ 59
    9.6    Sample SGML Open Entity Catalog for HTML ............. 61
    9.7    Character Entity Sets ................................ 62
    10     Security Considerations .............................. 64
    11     References ........................................... 64
    12     Acknowledgments ...................................... 66
    12.1   Authors' Addresses ................................... 66
    13     The HTML Coded Character Set ......................... 66
    14     Proposed Entities .................................... 69


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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.

    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. This specification
    corresponds to the capabilities of HTML in common use prior to
    June 1994 and referred to as ``HTML 2.0''.

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

        * Its document character set includes [ISO-8859-1] and

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        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.

            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:

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        * 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.


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, where as

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            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'.

    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

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            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 tail and
            the head.

    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.

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    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.

    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

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            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.

    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

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    concrete syntax determines how the sequence of characters of the
    document is mapped to a sequence of terminals in the grammar of
    the prologue.

    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

    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

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            |
            \-<P>
            |
            \-"Some text. "
            |
            \-EM
            |  |
            |  \-<EM>
            |  |
            |  \-"*wow*"
            |  |
            |  \-</EM>
            |
            \-</P>

    Some of the elements are delimited explicity 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").

    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

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    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
        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, you 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

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    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 delcaration
    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 `<'.


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

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    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

    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.

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    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 ->


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.


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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
    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

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    Media subtype name
            html

    Required parameters
            none

    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.


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

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    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 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

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    discussed in 8, "Forms".


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 allows the address of a document to
    be recorded in situations in which the document may be read out
    of context. The required HREF attribute specifies the base URI
    (see 7, "Hyperlinks") for navigating the document, overriding
    any context otherwise known to the user agent. The value of the
    HREF attribute must be an absolute URI.


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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.


5.2.4. Link: LINK

    The <LINK> element represents a hyperlink (see 7, "Hyperlinks").
    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,
    style sheets, document hierarchy 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.

    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.

    Attributes of the META element:

    HTTP-EQUIV
            binds the element to an HTTP header field. An HTTP

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            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'.


5.2.6. Next Id: NEXTID

    The <NEXTID> element is included for historical reasons only.
    HTML document 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>


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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.

    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.


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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 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 may limit or prevent the ability of the
            HTML user agent to faithfully render phrase markup.

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        * 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>


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

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        <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>


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 poem 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.


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5.6.1. Unordered List: UL, LI

    The <UL> represents a list of items -- typically 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
    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>


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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>


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>

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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 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 apropriate for
    multiple-line listings. For example:

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


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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.


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

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        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.


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

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            of relationship names.

    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
            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

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    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:

    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>


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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 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 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.


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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.

    A hyperlink is a relationship between two anchors, called the
    head and the tail of the hyperlink[DEXTER]. Each anchor is
    addressed, or uniquely identified, by an absolute Uniform
    Resource Identifier (URI), optionally followed by a '#' and a
    sequence of characters called a fragment identifier, as per
    [RELURL]. 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.

    An HTML user agent begins navigation with an absolute URI,
    called the base URI, and an HTML document that is a
    representation of the resource identified by the base URI.

    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 either directly by
    means of an absolute URI, or indirectly by means of a relative
    URI, which must be combined with the base URI as in [RELURL] to
    determine the address of the head anchor. The markup may also
    include fragment identifiers, separated from the URI by a '#'
    character.


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
    as in [URL].

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

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

    then the user agent uses the URI `http://host/icons/abc.gif' to
    access the resource linked from the <IMG> element.

    If the URI in the address of the head anchor is the same as the
    base URI, then the base document is sufficient as a
    representation of the resource. A user agent must _not_, for
    example, use any network information retrieval protocols to
    obtain a new representation of the resourse.

    For example, if the base uri is
    `http:'/www.w3.org/hypertext/WWW/TheProject.html/, then each of
    the following markup constructs indicates a link whose head and
    tail anchors have the same URI in their address:

    <a href="#xyz">
    <a href="../WWW/TheProject.html">
    <a href="./TheProject.html">
    <a href="TheProject.html">
    <a href="TheProject.html#z21">
    <a href="../../hypertext/WWW/TheProject.html">
    <a href="http://www.w3.org/hypertext/WWW/TheProject.html">


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. The base URI for navigation
    is taken from the head anchor by default; however, any <BASE>
    tag in the destination document overrides this default. The
    process of obtaining the destination document may also override
    the base URI, as in the case of an HTTP `URI:' header or
    redirection transaction.


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>

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    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.

    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.


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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'.


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").


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    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.

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

    Required attributes are:

    NAME
            name for the form field corresponding to this element.

    The optional attriubtes 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:


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    <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>


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

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    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>


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.

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    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>


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.


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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.

    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

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    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.

    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>

    The initial state of the form data set is:

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    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\ndef''

    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):

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


9. HTML Public Text


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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 1.29 1995/08/04 17:50:22 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">
]]>

<!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 an implemented inconsistently,
           and their use is deprecated. This feature test entity
           enables a document type definition that eliminates
           these features.
        -->


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<!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          -->
<!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

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        - 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"
        >
<!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 emphais                          -->
<!-- <CODE>     Source code phrase                      -->
<!-- <SAMP>     Sample text or characters               -->
<!-- <KBD>      Keyboard phrase, e.g. user input        -->
<!-- <VAR>      Variable phrase or substituable         -->
<!-- <CITE>     Name or title of cited work             -->

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

]]>

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<!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)*"
        -- <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

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        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"
        >

<!-- <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 -->

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<!-- <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">

<![ %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;"
        >


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

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

<!ATTLIST PLAINTEXT
        %SDAFORM; "Lit"
        >
]]>


<!--========== 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

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        %SDAFORM; "List"
        %SDAPREF; "<LHead>Directory</LHead>"
        >
<!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;"
        >

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

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

<!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>"

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        >

<!-- <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 [
        <!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)*>
<!ATTLIST TITLE
        %SDAFORM; "Ti"    >


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<!-- <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     >

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

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

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

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<!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
- -->

<!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'.

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    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>
        --
        >

<!-- 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"

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        -- 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;


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

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                 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 ""
                  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>


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        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 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 1.2 1994/11/30 23:45:18 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 Level 0: most general to most specific --
PUBLIC  "-//IETF//DTD HTML Level 0//EN"         html-0.dtd
PUBLIC  "-//IETF//DTD HTML 2.0 Level 0//EN"     html-0.dtd


        -- Ways to refer to Strict Level 2: most general to most specif\
c --
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 specif\
c --
PUBLIC  "-//IETF//DTD HTML Strict Level 1//EN"          html-1s.dtd
PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 1//EN"      html-1s.dtd

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        -- Ways to refer to Strict Level 0: most general to most specif\
c --
PUBLIC  "-//IETF//DTD HTML Strict Level 0//EN"          html-0s.dtd
PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 0//EN"      html-0s.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 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 sign
    &       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

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        $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 -->
<!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 -->

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<!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 -->
<!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]
            T. Berners-Lee. ``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]
            T. Berners-Lee, L. Masinter, and M. McCahill. ``Uniform
            Resource Locators (URL).'' RFC 1738, CERN, Xerox PARC,
            University of Minnesota, October 1994.
            <URL:ftp://ds.internic.net/rfc/rfc1738.txt>

    [HTTP]
            T. Berners-Lee, R. T. Fielding, and H. Frystyk Nielsen.
            ``Hypertext Transfer Protocol - HTTP/1.0.'' Work in
            Progress, MIT, UC Irvine, CERN, March 1995.
            <URL:ftp://ds.internic.net/internet-drafts/draft-ietf-http-v10-spec-00.ps>

    [MIME]
            N. Borenstein 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>

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

    [GOLD90]
            C. F. Goldfarb. ``The SGML Handbook.'' Y. Rubinsky, Ed.,
            Oxford University Press, 1990. <URL:>

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

    [IMEDIA]
            J. Postel. ``Media Type Registration Procedure.'',
            USC/ISI, March 1994.
            <URL:ftp://ds.internic.net/rfc/rfc1590.txt>

    [IANA]
            J. Reynolds and J. Postel. ``Assigned Numbers.'' STD 2,
            RFC 1700, USC/ISI, 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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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.
    Tel: +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.
    Fax: +1 (617) 258 8682
    Email: connolly@w3.org
    URI: http://www.w3.org/hypertext/WWW/People/Connolly/


13. The HTML Coded Character Set

    This list details the code positions and characters of the HTML

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    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
    &#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

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    &#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
    &#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

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    &#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
    &#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 -->

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    <!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 -->
    <!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 -->

Berners-Lee, Connolly                                          [Page 70]

INTERNET-DRAFT      Hypertext Markup Language - 2.0       August 8, 1995

    <!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 -->
    <!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                                          [Page 71]

