HTML Working Group T. Berners-Lee
INTERNET-DRAFT MIT/W3C
<draft-ietf-html-spec-02.txt> D. Connolly
Expires: In six months May 6, 1995
Hypertext Markup Language - 2.0
CONTENTS
1. Introduction
2. HTML as an Application of SGML
3. HTML as an Internet Media Type
4. Document Structure Elements
5. Character Content
6. Data Elements
7. Character Format Elements
8. Hyperlink Elements
9. Block Structuring Elements
10. Form-based Input Elements
11. HTML Public Text
12. Glossary
13. Bibliography
14. Appendices
15. Acknowledgments
Status of this Memo
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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; version=2.0"' Internet Media Type (RFC
1590) and MIME Content Type (RFC 1521) is defined by this
specification.
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.
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',
or `text/html; version=2.0'. 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
the behaviour of HTML user agents.
1.2.1. Documents
A document is a conforming HTML document only if:
* It is a conforming SGML document, and it conforms to
the HTML DTD (see 11.1, "HTML DTD")
* 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
agrees with ISO10646; that is, each code position
listed in 14.1, "The ISO-8859-1 Coded Character Set" is
included, and each code position in the document
character set is mapped to the same character as
ISO10646 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
ISO10646 repertoire. The crititcal distinction is that
numeric character references agree with ISO10646
regardless of how the document is encoded.
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
called out in notes like this throughout this
specification.
HTML documents should not contain these idioms, at
least until such time as support for them is widely
deployed.
The HTML DTD defines a standard HTML document type and
several variations, based on feature test entities:
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 enables a more
prescriptive document type definition that
eliminates those features.
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 an
implemented inconsistently, and their use is
deprecated. This feature test entity enables a
document type definition that eliminates these
features.
Documents generated by tranlation software or
editing software should not contain these idioms.
1.2.2. User Agents
An HTML user agent conforms to this specification if:
* It parses the characters of an HTML document into
data characters and markup as per [SGML].
* It supports the ISO-8859-1 character encoding scheme,
and processes each character in the ISO Latin Alphabet
Nr. 1 as specified in 5.1, "The ISO Latin 1 Character
Repertoire".
NOTE - To support non-western writing systems, HTML
user agents should support the Unicode-1-1-UTF-8 and
Unicode-1-1-UCS-2 encodings and as much of the
character repertoire of ISO10646 as is possible as
well.
* 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 behaviour of conforming user agents.
* It allows the user to traverse (or at least attempt
to traverse, resources permitting) all hyperlinks in an
HTML document.
* 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.
NOTE - In the interest of robustness and extensibility,
there are a number of widely deployed conventions for
handling non-conforming documents. See 3.2.1,
"Undeclared Markup Error Handling" for details.
2. HTML as an Application of SGML
HTML is an application of ISO Standard 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 11, "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.
2.1. 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.
The first production of the SGML grammar separates an SGML
document into three parts: an SGML declaration, a prologue,
and an instance. For the purposes of this specification, the
prologue is a DTD. This DTD describes another grammar: the
start symbol is given in the doctype declaration; the
terminals are data characters and tags, and the productions
are determined by the element declarations. The instance
must conform to the DTD, that is, it must be in the language
defined by this grammar.
The SGML declaration determines the lexicon of the grammar.
It specifies the document character set, which determines a
character repertoire that contains all characters that occur
in all text entities in the document, and the code positions
associated with those characters.
The SGML declaration also specifies the syntax-reference
character set of the document, and a few other parameters
that bind the abstract syntax of SGML to a concrete syntax.
This concrete syntax determines how the sequence of
characters of the document is mapped to a sequence of
terminals in the grammar of the prologue.
For example, consider the following document:
<!DOCTYPE html PUBLIC "-//IETF//DTD HTML 2.0//EN">
<title>Parsing Example</title>
<p>Some text. <em>*wow*</em></p>
An HTML user agent should use the SGML declaration is given
in 11.2, "SGML Declaration for HTML". According to the
document character set there,`*' refers to an asterisk
character.
The instance above is regarded as the following sequence of
terminals:
1. TITLE start-tag
2. data characters: ``Parsing Example''
3. TITLE end-tag
4. P start-tag
5. data characters ``Some text. ''
6. EM start-tag
7. ``*wow*''
8. EM end-tag
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' (11.1, "HTML DTD"). Hence the
terminals above parse as:
HTML
|
\-HEAD
| |
| \-TITLE
| |
| \-<TITLE>
| |
| \-"Parsing Example"
| |
| \-</TITLE>
|
\-BODY
|
\-P
|
\-<P>
|
\-"Some text. "
|
\-EM
| |
| \-<EM>
| |
| \-"*wow*"
| |
| \-</EM>
|
\-</P>
2.2. 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 ISO-646-IRV character repertoire. Data
characters are drawn from the document character set (see 5,
"Character Content").
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.
2.2.1. 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
also map to single-character strings, via the document
character set. Each reference to one of the general entities
defined in the HTML DTD also maps to a single-character
string.
For example,
abc<def => "abc","<","def"
abc<def => "abc","<","def"
Note that the terminating semicolon is only necessary when
the character following the reference would otherwise be
recognized as markup:
abc < def => "abc ","<"," def"
abc < def => "abc ","<"," def"
And note that an ampersand is only recognized as markup when
it is followed by a letter or 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
& & & Ampersand
< < < Less than
> > > Greater than
NOTE - There are SGML mechanisms, CDATA and RCDATA, to
allow most `<', `>', and `&' characters to be entered
without the use of entity references. Because these
features tend to be used and implemented
inconsistently, and because they conflict with
techinques for reducing HTML to 7 bit ASCII for
transport, they are not used in this version of the
HTML DTD.
2.2.2. 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, 11.1, "HTML
DTD" for full details.
NOTE - The SGML declaration for HTML specifies SHORTTAG
YES, which means that there are other valid syntaxes
for tags, such as NET tags, `<EM/.../'; empty start
tags, `<>'; and empty end-tags, `</>'. Until support
for these idioms is widely deployed, their use is
strongly discouraged.
2.2.3. Names
A name consists of a letter followed by up to 71 letters,
digits, periods, or hyphens. Element names are not case
sensitive, but entity names are. For example,
`<BLOCKQUOTE>', `<BlockQuote>', and `<blockquote>' are
equivalent, whereas `&' is different from `&'.
In a start-tag, the element name must immediately follow the
tag open delimiter `<'.
2.2.4. Attributes
In a start-tag, white space and attributes are allowed
between the element name and the closing delimiter. An
attribute typically consists of an attribute name, an equal
sign, and a value, though some attributes may be just a
value. 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.
* A name token (a sequence of letters, digits, periods,
or hyphens)
In this example, img is the element name, `src' is the
attribute name, and `http://host/dir/file.gif' is the
attribute value:
<img src="http://host/dir/file.gif">
NOTE - Some historical implementations consider any
occurrence of the `>' character to signal the end of a
tag. For ompatibility with such implementations, when
`>' appears in an attribute value, it should be
represented with a numeric character reference, such as
in: `<IMG SRC="eq1.jpg" alt="a>b">'.
A useful technique for computing an attribute value literal
for a given string is to replace each quote and space
character by an entity reference or numeric character
reference as follows:
ENTITY NUMERIC
CHARACTER REFERENCE CHAR REF CHARACTER DESCRIPTION
TAB 	 Tab
LF Line Feed
CR Carriage Return
  Space
" " " Quotation mark
& & & Ampersand
For example:
<IMG SRC="image.jpg" alt="First "real" example">
NOTE - Some historical implementations allow any
character except space or `>' in a name token.
Attributes values must be quoted only if they don't
satisfy the syntax for a name token.
Note that the SGML declaration in section 13.3 limits the
length of an attribute value to 1024 characters.
Attributes such as ISMAP and COMPACT, may be written using a
minimized syntax. The markup:
<UL COMPACT="compact">
can be written using a minimized syntax:
<UL COMPACT>
NOTE - Some historical implementations only understand
the minimized syntax.
2.2.5. Comments
To include comments in an HTML document that will be
eliminated in the mapping to terminals, surround them with
`<!--' and `-->'. After the comment delimiter, all text up
to the next occurrence of `-->' is ignored. Hence comments
cannot be nested. White space is allowed between the closing
`--' and `>', but not between the opening `<!' and `--'.
For example:
<HEAD>
<TITLE>HTML Guide: Recommended Usage</TITLE>
<!-- $Id: html-sgml.sgm,v 1.4 1995/05/06 01:44:46 connolly Exp $ -->
</HEAD>
NOTE - Some historical HTML implementations incorrectly
consider any `>' character to be the termination of a
comment.
2.2.6. Example HTML Document
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//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 </P>
end tag has been omitted.
<P>
<IMG SRC ="triangle.xbm" alt="Warning: ">
Be sure to read these <b>bold instructions</b>.
</BODY></HTML>
3. 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 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). Conforming HTML
user agents should support form entry and submission.
3.1. text/html media type
This specification defines the Internet Media Type[IMEDIA]
(formerly referred to as the Content Type[MIME]) called
`text/html'. The following is to be registered with [IANA].
Media Type name
text
Media subtype
name
html
Required
parameters
none
Optional
parameters
version, charset
Encoding
considerations
any encoding is allowed
Security
considerations
see 3.3, "Security Considerations"
The optional parameters are defined as follows:
Version
To help avoid future compatibility problems, the
version parameter may be used to give the version
number of the specification to which the document
conforms. The version number appears at the front
of this document and within the public identifier
of the HTML DTD. This specification defines
version 2.0. There is no 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.
3.2. 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.
3.2.1. Undeclared Markup Error Handling
To facilitate experimentation and interoperability between
implementations of various versions of HTML, the installed
base of HTML user agents supports a superset of the HTML 2.0
language by reducing it to HTML 2.0: markup in the form of a
start-tag or end-tag whose generic identifier is not
declared is mapped to nothing during tokenization.
Undeclared attributes are treated similarly. The entire
attribute specification of an unknown attribute (i.e., the
unknown attribute and its value, if any) should be ignored.
On the 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 α and β be finite sets.
=> "Let α and β 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 is
not conforming to this specification.
3.2.2. 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 10, 13.
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 CR LF
combination. 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 expect to treat any of the three common
representations of end-of-line as starting a new line.
3.3. 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 the URI specification 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 -- should be aware and make their users
aware of the lack of confidentiality.
>
4. Document Structure Elements
To identify information as an HTML document conforming to
this specification, each document should start with the
prologue:
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
NOTE - If the body of a text/html body part does not
begin with a document type declaration, an HTML user
agent should infer the above document type declaration.
HTML user agents are required to support the above document
type declaration, the following document type declarations,
and no others.
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Strict//EN">
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML Strict//EN">
In particular, they may support other formal public
identifiers, or document types altogether. They may support
an internal declaration subset with supplemental entity,
element, and other markup declarations, or they may not.
4.1. HTML Document Element
<HTML> ... </HTML> Level 0
The HTML document element is organized as a head and a body,
much like a memo or a mail message. Within the head, you can
specify the title and other information about the document.
Within the body, you can structure text into paragraphs and
lists, as well as highlight phrases and create links, using
HTML elements.
NOTE - The start and end tags for HTML, Head, and Body
elements are omissible; however, this is not
recommended since the head/body structure allows an
implementation to determine certain properties of a
document, such as the title, without parsing the entire
document.
<
4.2. Head
<HEAD> ... </HEAD> Level 0
The head of an HTML document is an unordered collection of
information about the document. The Title element is
required.
<HEAD>
<TITLE>Introduction to HTML</TITLE>
</HEAD>
4.3. Body
<BODY> ... </BODY> Level 0
The Body element identifies the body component of an HTML
document. Specifically, the body of a document may contain
links, text, and formatting information within <BODY> and
</BODY> tags.
4.4. Title
<TITLE> ... </TITLE> Level 0
Every HTML document must contain a Title element. The title
should identify the contents of the document in a global
context, and may be used in history lists and as a label for
the window displaying the document. Unlike headings, titles
are not rendered in the text of a document itself.
The Title element must occur within the head of the
document, and must not contain anchors, paragraph tags, or
highlighting. Only one title is allowed in a document.
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. Also keep in mind that a short title,
such as Introduction, may be meaningless out of
context. An example of a meaningful title might be
``Introduction to HTML Elements.''
4.5. Base
<BASE> Level 0
The Base element allows the URI of the document itself to be
recorded in situations in which the document may be read out
of context. URIs within the document may be in a ``partial''
form relative to this base address[RELURL].
The Base element has one attribute, HREF, which identifies
the absolute base URI.
4.6. Isindex
<ISINDEX> Level 0
The Isindex element tells the interpreter that the document
is an index. This means that the reader may request a
keyword search on the resource by adding a question mark to
the end of the document address, followed by a list of
keywords separated by plus signs.
The Isindex element is usually generated by the network
server from which the document was obtained via a URI. The
server must have a search engine that supports this feature
for the resource. If the document URI is unknown to the
interpreter, <isindex> must be ignored.
4.7. Link
<LINK> Level 0
The Link element indicates a relationship between the
document and some other object. A document may have any
number of Link elements.
The Link element is empty (does not have a closing tag), but
takes the same attributes as the Anchor element.
Typical uses are to indicate authorship, related indexes and
glossaries, older or more recent versions, etc. Links can
indicate a static tree structure in which the document was
authored by pointing to a ``parent'' and ``next'' and
``previous'' document, for example.
Servers may also allow links to be added by those who do not
have the right to alter the body of a document.
4.8. Meta
<META> Level 0
The META element is used within the HEAD element to embed
document metainformation not defined by other HTML elements.
META elements can be extracted by servers and/or clients for
use in identifying, indexing, and cataloging specialized
document metainformation.
Although it is generally preferable to use named elements
which have well-defined semantics for each type of
metainformation (e.g. TITLE), the META element is provided
for situations where strict SGML parsing is necessary and
the local DTD is not extensible. HTML interpreters may use
the META element's content if they recognize and understand
the semantics identified by the NAME or HTTP-EQUIV
attributes, and may treat the content as metainformation
(and not render it) even when they do not recognize the
name.
In addition, HTTP servers may wish to read the content of
the document HEAD to generate header fields corresponding to
any elements defining a value for the attribute HTTP-EQUIV.
Note, however, that the method by which the server extracts
document metainformation is not part of this specification,
nor can it be assumed by authors that any given server will
be capable of extracting it. The META element only provides
an extensible mechanism for identifying and embedding
document metainformation - how it may be used is up to the
individual server implementation and the HTML interpreter.
Attributes of the META element:
HTTP-EQUIV
This attribute binds the element to an HTTP header
field. It means that if you know the semantics of
the HTTP header field named by this attribute,
then you can process the contents based on a
well-defined syntactic mapping, whether or not
your DTD tells you anything about it. HTTP header
field names are not case sensitive. If not
present, the attribute NAME should be used to
identify this metainformation and the content
should not be used within an HTTP response header.
NAME
Metainformation name. If the NAME attribute is not
present, the name can be assumed to be equal to
the value of HTTP-EQUIV.
CONTENT
The metainformation content to be associated with
the given name. 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.
Examples
If the document contains:
<META HTTP-EQUIV="Expires"
CONTENT="Tue, 04 Dec 1993 21:29:02 GMT">
<meta http-equiv="Keywords" CONTENT="Fred, Barney">
<META HTTP-EQUIV="Reply-to"
content="fielding@ics.uci.edu (Roy Fielding)">
then the server (if so configured) may include the following
headers:
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.
When the HTTP-EQUIV attribute is not present, the server
should not generate an HTTP response header for the
metainformation; e.g.,
<META NAME="IndexType" CONTENT="Service">
would never generate an HTTP response header, but would
still allow HTML interpreters to identify and make use of
that metainformation.
The Meta element should never be used to define information
that should be associated with an existing HTML element. An
example of an inappropriate use of the Meta element is:
<META NAME="Title" CONTENT="The Etymology of
Dunsel">
Do not name an HTTP-EQUIV equal to a response header that
should normally only be generated by the HTTP server.
Example names that are inappropriate include ``Server'',
``Date'', and ``Last-modified'' - the exact list of
inappropriate names is dependent on the particular server
implementation. We recommend that servers ignore any META
elements which specify HTTP-equivalents which are equal
(case-insensitively) to their own reserved response headers.
4.9. Nextid
<NEXTID> Level 0
The Nextid element is a parameter read and generated by text
editing software to create unique identifiers. This tag
takes a single attribute which is the next document-wide
alpha- numeric identifier to be allocated of the form z123:
<NEXTID N=Z27>
When modifying a document, existing anchor identifiers
should not be reused, as these identifiers may be referenced
by other documents. Human writers of HTML usually use
mnemonic alphabetical identifiers.
HTML interpreters may ignore the Nextid element. Support for
the Nextid element does not impact HTML interpreters in any
way.
5. Character Content
An HTML user agent should present the body of an HTML
document as a collection of typeset paragraphs and
preformatted text. Except for the <PRE> element, 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.
5.1. The ISO Latin 1 Character Repertoire
The minimum character repertoire supported by all conforming
HTML user agents is Latin Alphabet Nr. 1, or simply Latin-1.
Latin-1 includes characters from most Western European
languages, as well as a number of control characters.
Latin-1 also includes a non-breaking space, a soft hyphen
indicator, 93 graphical characters, 8 unassigned characters,
and 25 control characters.
NOTE - Use the non-breaking space and soft hyphen
indicator characters is discouraged because support for
them is not widely deployed.
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 HTML, only three control characters are allowed:
Horizontal Tab (HT, encoded as 9 decimal in US-ASCII and
ISO-8859-1), Carriage Return, and Line Feed.
The HTML DTD references the Added Latin 1 entity set, to
allow mnemonic representation of Latin 1 characters using
only the widely supported ASCII character repertoire. For
example:
Kurt Gödel was a famous logician and mathematician.
See 11.4.2, "ISO Latin 1 Character Entity Set" for a table
of the ``Added Latin 1'' entities, and 14.1, "The ISO-8859-1
Coded Character Set" for a table of the code positions of
ISO-8859-1.
6. Data Elements
6.1. Line Break
<BR> Level 0
The Line Break element specifies that a new line must be
started at the given point. A new line indents the same as
that of line-wrapped text.
Example of use:
<P> Pease porridge hot<BR>
Pease porridge cold<BR>
Pease porridge in the pot<BR>
Nine days old.
6.2. Horizontal Rule
<HR> Level 0
A Horizontal Rule element is a divider between sections of
text such as a full width horizontal rule or equivalent
graphic.
Example of use:
<HR>
<ADDRESS>February 8, 1995, CERN</ADDRESS>
</BODY>
6.3. Image
<IMG> Level 0
The Image element is used to incorporate in-line graphics
(typically icons or small graphics) into an HTML document.
This element cannot be used for embedding other HTML text.
HTML interpreters that cannot render in-line images ignore
the Image element unless it contains the ALT attribute. Note
that some HTML interpreters can render linked graphics but
not in-line graphics. If a graphic is essential, you may
want to create a link to it rather than to put it in-line.
If the graphic is not essential, then the Image element is
appropriate.
The Image element, which is empty (no closing tag), has
these attributes:
ALIGN
The ALIGN attribute accepts the values TOP or
MIDDLE or BOTTOM, which specifies if the following
line of text is aligned with the top, middle, or
bottom of the graphic.
ALT
Optional text as an alternative to the graphic for
rendering in non-graphical environments. Alternate
text should be provided whenever the graphic is
not rendered. Alternate text is mandatory for
Level 0 documents. Example of use:
<IMG SRC="triangle.xbm" ALT="Warning:"> Be sure
to read these instructions.
ISMAP
The ISMAP (is map) attribute identifies an image
as an image map. Image maps are graphics in which
certain regions are mapped to URIs. By clicking on
different regions, different resources can be
accessed from the same graphic. Example of use:
<A HREF="http://machine/htbin/imagemap/sample">
<IMG SRC="sample.xbm" ISMAP>
</A>
SRC
The value of the SRC attribute is the URI of the
document to be embedded; only images can be
embedded, not HTML text. Its syntax is the same as
that of the HREF attribute of the `<A>' tag. SRC
is mandatory. Image elements are allowed within
anchors.
Example of use:
<IMG SRC="triangle.xbm">Be sure to read these
instructions.
7. Character Format Elements
Character format elements are used to specify either the
logical meaning or the physical appearance of marked text
without causing a paragraph break. Like most other elements,
character format elements include both opening and closing
tags. Only the characters between the tags are affected:
This is <EM>emphasized</EM> text.
Character format tags may be ignored by minimal HTML
applications.
Character format tags are interpreted from left to right as
they appear in the flow of text. Level 1 interpreters must
render highlighted text 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.
Character format elements may be nested within the content
of other character format elements; however, HTML
interpreters are not required to render nested character
format elements distinctly from non-nested elements:
plain <B>bold <I>italic</I></B> may the rendered
the same as plain <B>bold </B><I>italic</I>
7.1. Semantic Format Elements
Note that typical renderings for semantic format elements
vary between applications. If a specific rendering is
necessary - for example, when referring to a specific text
attribute as in ``The italic parts are mandatory'' - a
physical formating element can be used to ensure that the
intended rendered is used where possible.
Note that different sematic elements may be rendered in the
same way.
7.1.1. Citation
<CITE>...</CITE> Level 1
The Citation element specifies a citation, typically
rendered as italics.
7.1.2. Code
<CODE> ... </CODE> Level 1
The Code element indicates an example of code, typically
rendered in a monospaced font. This should not be confused
with the Preformatted Text element.
7.1.3. Emphasis
<EM> ... </EM> Level 1
The Emphasis element indicates typographic emphasis,
typically rendered as italics.
7.1.4. Keyboard
<KBD> ... </KBD> Level 1
The Keyboard element indicates text typed by a user,
typically rendered in a monospaced font. This is commonly
used in instruction manuals.
7.1.5. Sample
<SAMP> ... </SAMP> Level 1
The Sample element indicates a sequence of literal
characters, typically rendered in a monospaced font.
7.1.6. Strong
<STRONG> ... </STRONG> Level 1
The Strong element indicates strong typographic emphasis,
typically rendered in bold.
7.1.7. Variable
<VAR> ... </VAR> Level 1
The Variable element indicates a variable name, typically
rendered as italic.
7.2. Physical Format Elements
Physical format elements are used to specify the format of
marked text.
7.2.1. Bold
<B> ... </B> Level 1
The Bold element specifies that the text should be rendered
in boldface, where available. Otherwise, an alternative
mapping is allowed.
7.2.2. Italic
<I> ... </I> Level 1
The Italic element specifies that the text should be
rendered in an italic font, where available. Otherwise, an
alternative mapping is allowed.
7.2.3. Teletype
<TT> ... </TT> Level 1
The Teletype element specifies that the text should be
rendered in a fixed-width typewriter font.
8. Hyperlink Elements
8.1. Anchor
<A> ... </A> Level 0
An anchor is a marked section of text that is the start
and/or destination of a hypertext link. Anchor elements are
defined by the `<A>' tag. The `<A>' tag accepts several
attributes; at least one of the NAME and HREF attributes is
required.
Attributes of the `<A>' tag:
8.1.1. HREF
If the HREF attribute is present, the text between the
opening and closing anchor tags becomes hypertext. If this
hypertext is selected by readers, they are moved to another
document, or to a different location in the current
document, whose network address is defined by the value of
the HREF attribute.
Example:
See <A HREF="http://www.hal.com/">HaL</A>'s
information for more details.
In this example, selecting ``HaL'' takes the reader to a
document at http://www.hal.com. The format of the network
address is specified in the URI specification for print
readers.
With the HREF attribute, the form HREF=``#identifier'' can
refer to another anchor in the same document.
Example:
The <A HREF="#glossary">glossary</A> defines
terms used in this document.
In this example, selecting ``glossary'' takes the reader to
another anchor (i.e., <A NAME=``glossary''>Glossary</A>) in
the same document. The NAME attribute is described below. If
the anchor is in another document, the HREF attribute may be
relative to the document's address or the specified base
address (see 4.5, "Base").
8.1.2. NAME
If present, the NAME attribute allows the anchor to be the
target of a link. The value of the NAME attribute is an
identifier for the anchor. Identifiers are arbitrary strings
but must be unique within the HTML document.
Example of use:
<A NAME="coffee">Coffee</A> is an example of ...
... An example of this is <A HREF="#coffee">coffee</A>.
Another document can then make a reference explicitly to
this anchor by putting the identifier after the address,
separated by a hash sign:
<A HREF="drinks.html#coffee">
8.1.3. TITLE
The TITLE attribute is informational only. If present, the
TITLE attribute should provide the title of the document
whose address is given by the HREF attribute. The TITLE
attribute is useful for at least two reasons. The HTML
interpreter may display the title of the document prior to
retrieving it, 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. Another reason is that documents
that are not marked up text, such as graphics, plain text
and Gopher menus, do not have titles. The TITLE attribute
can be used to provide a title to such documents. When using
the TITLE attribute, the title should be valid and unique
for the destination document.
8.1.4. REL
The REL attribute gives the relationship(s) described by the
hypertext link from the anchor to the target. The value is a
whitespace-separated list of relationship names.
Relationship names and their semantics will be registered by
the W3 Consortium. The default relationship is void. The REL
attribute is only used when the HREF attribute is present.
8.1.5. REV
The REV attribute is the same as the REL attribute, but the
semantics of the link type 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.
8.1.6. URN
If present, the URN attribute specifies a uniform resource
name (URN) for a target document. The format of URNs is
under discussion (1995) by various working groups of the
Internet Engineering Task Force.
8.1.7. METHODS
The METHODS attributes of anchors and links provide
information about the functions that the user may perform on
an object. These are more accurately given by the HTTP
protocol when it is used, but it may, for similar reasons as
for the TITLE attribute, be useful to include the
information in advance in the link. For example, the HTML
interpreter may chose a different rendering as a function of
the methods allowed; for example, something that is
searchable may get a different icon.
The value of the METHODS attribute is a whitespace-separated
list of HTTP methods supported by the object for public use.
9. Block Structuring Elements
The following elements may be included in the body of an
HTML document:
9.1. Paragraph
<P> ... </P> Level 0
The Paragraph element indicates a paragraph. The exact
indentation, leading space, etc. of a paragraph is not
defined 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. This is typically not the case
within the Address element and is never the case within the
Preformatted Text element. With some HTML interpreters, the
first line in a paragraph is indented.
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>
9.2. Preformatted Text
<PRE> ... </PRE> Level 0
The Preformatted Text element presents blocks of text in
fixed-width font, and so is suitable for text that has been
formatted on screen.
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 interpreter to
select a suitable font and indentation. If the WIDTH
attribute is not present, a width of 80 characters is
assumed. Where the WIDTH attribute is supported, widths of
40, 80 and 132 characters should be presented optimally,
with other widths being rounded up.
Within preformatted text:
* Line breaks within the text are rendered as a move to
the beginning of the next line.
* Anchor elements and character highlighting elements
may be used.
* Elements that define paragraph formatting (headings,
address, etc.) must not be used.
* The horizontal tab character (encoded in US-ASCII and
ISO-8859-1 as decimal 9) 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. Its use is not recommended however.
NOTE - Som historical documents contain <P> tags in
<PRE> elements. User agents are engcouraged to treat
this a 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.
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.
Example of use:
<PRE WIDTH="80">
This is an example line.
</PRE>
NOTE - Within a Preformatted Text element, the
constraint that the rendering must be on a fixed
horizontal character pitch may limit or prevent the
ability of the HTML interpreter to faithfully render
character formatting elements.
9.3. Address
<ADDRESS> ... </ADDRESS> Level 0
The Address element specifies such information as address,
signature and authorship, often at the top or bottom of a
document.
Typically, an Address is rendered in an italic typeface and
may be indented. The Address element implies a paragraph
break before and after.
Example of use:
<ADDRESS>
Newsletter editor<BR>
J.R. Brown<BR>
JimquickPost News, Jumquick, CT 01234<BR>
Tel (123) 456 7890
</ADDRESS>
9.4. Blockquote
<BLOCKQUOTE> ... </BLOCKQUOTE> Level 0
The Blockquote element is used to contain text quoted from
another source.
A typical rendering might be a slight extra left and right
indent, and/or italic font. The Blockquote element causes a
paragraph break, and 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.
9.5. Headings
<H1> ... </H1> through <H6> ... </H6> Level 0
HTML defines six levels of heading. A Heading element
implies all the font changes, paragraph breaks before and
after, and white space necessary to render the heading.
The highest level of headings is H1, followed by H2 ... H6.
Example of use:
<H1>This is a heading</H1>
Here is some text
<H2>Second level heading</H2>
Here is some more text.
The rendering of headings is determined by the HTML
interpreter, but typical renderings are:
<H1> ... </H1>
Bold, very-large font, centered. One or two blank
lines above and below.
<H2> ... </H2>
Bold, large font, flush-left. One or two blank
lines above and below.
<H3> ... </H3>
Italic, large font, slightly indented from the
left margin. One or two blank lines above and
below.
<H4> ... </H4>
Bold, normal font, indented more than H3. One
blank line above and below.
<H5> ... </H5>
Italic, normal font, indented as H4. One blank
line above.
<H6> ... </H6>
Bold, indented same as normal text, more than H5.
One blank line above.
Although heading levels can be skipped (for example, from H1
to H3), this practice is discouraged as skipping heading
levels may produce unpredictable results when generating
other representations from HTML.
9.6. List Elements
HTML supports several types of lists, all of which may be
nested.
9.6.1. Definition List
<DL> ... </DL> Level 0
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.
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 (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.
Single occurrences of a <DT> tag without a subsequent <DD>
tag are allowed, and have the same significance as if the
<DD> tag had been present with no text.
The opening list tag must be <DL> and must be immediately
followed by the first term (<DT>).
The definition list type can take the COMPACT attribute,
which suggests that a compact rendering be used, because the
list items are small and/or the entire list is large.
Unless you provide the COMPACT attribute, the HTML
interpreter may leave white space between successive DT, DD
pairs. The COMPACT attribute may also reduce the width of
the left-hand (DT) column.
If using the COMPACT attribute, the opening list tag must be
<DL COMPACT>, which must be immediately followed by the
first <DT> tag:
<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>
9.6.2. Directory List
<DIR> ... </DIR> Level 0
A Directory List element is used to present a list of items
containing up to 20 characters each. Items in a directory
list may be arranged in columns, typically 24 characters
wide. If the HTML interpreter can optimize the column width
as function of the widths of individual elements, so much
the better.
A directory list must begin with the <DIR> tag which is
immediately followed by a <LI> (list item) tag:
<DIR>
<LI>A-H<LI>I-M
<LI>M-R<LI>S-Z
</DIR>
9.6.3. Menu List
<MENU> ... </MENU> Level 0
A menu list is a list of items with typically one line per
item. The menu list style is more compact than the style of
an unordered list.
A menu list must begin with a <MENU> tag which is
immediately followed by a <LI> (list item) tag:
<MENU>
<LI>First item in the list.
<LI>Second item in the list.
<LI>Third item in the list.
</MENU>
9.6.4. Ordered List
<OL> ... </OL> Level 0
The Ordered List element is used to present a numbered list
of items, sorted by sequence or order of importance.
An ordered list must begin with the <OL> tag which is
immediately followed by a <LI> (list item) tag:
<OL>
<LI>Click the Web button to open the Open the URI window.
<LI>Enter the URI number in the text field of the Open URI
window. The Web document you specified is displayed.
<LI>Click highlighted text to move from one link to another.
</OL>
The Ordered List element can take the COMPACT attribute,
which suggests that a compact rendering be used.
9.6.5. Unordered List
<UL> ... </UL> Level 0
The Unordered List element is used to present a list of
items which is typically separated by white space and/or
marked by bullets.
An unordered list must begin with the <UL> tag which is
immediately followed by a <LI> (list item) tag:
<UL>
<LI>First list item
<LI>Second list item
<LI>Third list item
</UL>
10. Form-based Input Elements
Forms are created by placing input fields within paragraphs,
preformatted/literal text, and lists. This gives
considerable flexibility in designing the layout of forms.
The following elements are used to create forms:
FORM
A form within a document.
INPUT
One input field.
OPTION
One option within a Select element.
SELECT
A selection from a finite set of options.
TEXTAREA
A multi-line input field.
Each variable field is defined by an Input, Textarea, or
Option element and must have an NAME attribute to identify
its value in the data returned when the form is submitted.
Example of use (a questionnaire form):
<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>
In the example above, the <P> and <UL> tags have been used
to lay out the text and input fields. The HTML interpreter
is responsible for handling which field will currently get
keyboard input.
Many platforms have existing conventions for forms, for
example, using Tab and Shift keys to move the keyboard focus
forwards and backwards between fields, and using the Enter
key to submit the form. In the example, the SUBMIT and RESET
buttons are specified explicitly with special purpose
fields. The SUBMIT button is used to e-mail the form or send
its contents to the server as specified by the ACTION
attribute, while RESET resets the fields to their initial
values. When the form consists of a single text field, it
may be appropriate to leave such buttons out and rely on the
Enter key.
The Input element is used for a large variety of types of
input fields.
To let users enter more than one line of text, use the
Textarea element.
The radio button and checkbox types of input field can be
used to specify multiple choice forms in which every
alternative is visible as part of the form. An alternative
is to use the Select element which is typically rendered in
a more compact fashion as a pull down combo list.
10.1. Form
<FORM> ... </FORM> Level 2
The Form element is used to delimit a data input form. There
can be several forms in a single document, but the Form
element can't be nested.
The ACTION attribute is a URI specifying the location to
which the contents of the form is submitted to elicit a
response. If the ACTION attribute is missing, the URI of the
document itself is assumed. The way data is submitted varies
with the access protocol of the URI, and with the values of
the METHOD and ENCTYPE attributes.
In general:
* the METHOD attribute selects variations in the
protocol.
* the ENCTYPE attribute specifies the format of the
submitted data in case the protocol does not impose a
format itself.
When the ACTION attribute is set to an HTTP URL, the METHOD
attribute must be set to an HTTP method [HTTP]. The default
method is GET, although for many applications the POST
method is preferred. With the POST method, the ENCTYPE
attribute is a media type specifying the format of the
posted data; the default is
``application/x-www-form-urlencoded''.
The submitted contents of the form logically consist of
name/value pairs. The names are usually equal to the NAME
attributes of the various interactive elements in the form.
NOTE - The names are not guaranteed to be unique keys,
nor are the names of form elements required to be
distinct. The values encode the user's input to the
corresponding interactive elements. Fields with null
values may be omitted from the returned list of
name/value pairs, whereas those with non-null values
should be included (even if the value was not altered
by the user). In particular, unselected radio buttons
and checkboxes should be excluded from the contents
list.
10.2. Input
<INPUT> Level 2
The Input element represents a field whose contents may be
edited by the user.
Attributes of the Input element:
ALIGN
Vertical alignment of the image. For use only with
TYPE=IMAGE. The possible values are exactly the
same as for the ALIGN attribute of the image
element.
CHECKED
Indicates that a checkbox or radio button is
selected. Unselected checkboxes and radio buttons
do not return name/value pairs when the form is
submitted.
MAXLENGTH
Indicates the maximum number of characters that
can be entered into a text field. This can be
greater than specified by the SIZE attribute, in
which case the field will scroll appropriately.
The default number of characters is unlimited.
NAME
Symbolic name used when transferring the form's
contents. The NAME attribute is required for most
input types and is normally used to provide a
unique identifier for a field, or for a logically
related group of fields.
SIZE
Specifies the size or precision of the field
according to its type. For example, to specify a
field with a visible width of 24 characters:
INPUT TYPE=text SIZE="24"
SRC
A URI specifying an image. For use only with
TYPE=IMAGE.
TYPE
Defines the type of data the field accepts.
Defaults to free text. Several types of fields can
be defined with the type attribute:
CHECKBOX
Used for simple Boolean attributes, or for
attributes that can take multiple values at the
same time. The latter is represented by a number
of checkbox fields each of which has the same
name. Each selected checkbox generates a separate
name/value pair in the submitted data, even if
this results in duplicate names. The default value
for checkboxes is ``on''.
HIDDEN
No field is presented to the user, but the content
of the field is sent with the submitted form. This
value may be used to transmit state information
about client/server interaction.
IMAGE
An image field upon which you can click with a
pointing device, causing the form to be
immediately submitted. The coordinates of the
selected point are measured in pixel units from
the upper-left corner of the image, and are
returned (along with the other contents of the
form) in two name/value pairs. The x-coordinate is
submitted under the name of the field with ``.x''
appended, and the y-coordinate is submitted under
the name of the field with ``.y'' appended. Any
VALUE attribute is ignored. The image itself is
specified by the SRC attribute, exactly as for the
Image element.
NOTE - In a future version of the HTML specification,
the IMAGE functionality may be folded into an enhanced
SUBMIT field.
PASSWORD
The same as the TEXT attribute, except that text
is not displayed as it is entered.
RADIO
Used for attributes that accept a single value
from a set of alternatives. Each radio button
field in the group should be given the same name.
Only the selected radio button in the group
generates a name/value pair in the submitted data.
Radio buttons require an explicit VALUE attribute.
RESET
A button that when pressed resets the form's
fields to their specified initial values. The
label to be displayed on the button may be
specified just as for the SUBMIT button.
SUBMIT
A button that when pressed submits the form. You
can use the VALUE attribute to provide a
non-editable label to be displayed on the button.
The default label is application-specific. If a
SUBMIT button is pressed in order to submit the
form, and that button has a NAME attribute
specified, then that button contributes a
name/value pair to the submitted data. Otherwise,
a SUBMIT button makes no contribution to the
submitted data.
TEXT
Used for a single line text entry fields. Use in
conjunction with the SIZE and MAXLENGTH
attributes. Use the Textarea element for text
fields which can accept multiple lines.
VALUE
The initial displayed value of the field, if it
displays a textual or numerical value; or the
value to be returned when the field is selected,
if it displays a Boolean value. This attribute is
required for radio buttons.
10.3. Option
<OPTION> Level 2
The Option element can only occur within a Select element.
It represents one choice, and can take these attributes:
SELECTED
Indicates that this option is initially selected.
VALUE
When present indicates the value to be returned if
this option is chosen. The returned value defaults
to the contents of the Option element.
The contents 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.
10.4. Select
<SELECT NAME=... > ... </SELECT> Level 2
The Select element allows the user to chose one of a set of
alternatives described by textual labels. Every alternative
is represented by the Option element. Attributes are:
MULTIPLE
The MULTIPLE attribute is needed when users are
allowed to make several selections, e.g. <SELECT
MULTIPLE>.
NAME
Specifies the name that will submitted as a
name/value pair.
SIZE
Specifies the number of visible items. If this is
greater than one, then the resulting form control
will be a list.
The Select element is typically rendered as a pull down or
pop-up list. For example:
<SELECT NAME="flavor">
<OPTION>Vanilla
<OPTION>Strawberry
<OPTION>Rum and Raisin
<OPTION>Peach and Orange
</SELECT>
If no option is initially marked as selected, then the first
item listed is selected.
10.5. Text Area
<TEXTAREA> ... </TEXTAREA> Level 2
The Textarea element lets users enter more than one line of
text. For example:
<TEXTAREA NAME="address" ROWS=64 COLS=6>
HaL Computer Systems
1315 Dell Avenue
Campbell, California 95008
</TEXTAREA>
The text up to the end tag (</TEXTAREA>) is used to
initialize the field's value. This end tag is always
required even if the field is initially blank. When
submitting a form, lines in a TEXTAREA should be terminated
using CRLF.
In a typical rendering, the ROWS and COLS attributes
determine the visible dimension of the field in characters.
The field is rendered in a fixed-width font. HTML
interpreters should allow text to extend beyond these limits
by scrolling as needed.
NOTE - In the initial design for forms, multi-line text
fields were supported by the Input element with
TYPE=TEXT. Unfortunately, this causes problems for
fields with long text values. SGML's default (Reference
Quantity Set) limits the length of attribute literals
to only 240 characters. The HTML 2.0 SGML declaration
increases the limit to 1024 characters.
11. HTML Public Text
11.1. HTML DTD
This is the Document Type Definition for the HyperText
Markup Language.
<!-- html.dtd
Document Type Definition for the HyperText Markup Language
(HTML DTD)
5
$Id: html.dtd,v 1.25 1995/03/29 18:53:13 connolly Exp $
Author: Daniel W. Connolly <connolly@w3.org>
See Also: html.decl, html-0.dtd, html-1.dtd
10 http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html
-->
<!ENTITY % HTML.Version
"-//IETF//DTD HTML 2.0//EN"
15
-- Typical usage:
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
<html>
20 ...
</html>
--
>
25
<!--============ Feature Test Entities ========================-->
<!ENTITY % HTML.Recommended "IGNORE"
-- Certain features of the language are necessary for
30 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.
35 -->
<![ %HTML.Recommended [
<!ENTITY % HTML.Deprecated "IGNORE">
]]>
40
<!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,
45 and their use is deprecated. This feature test entity
enables a document type definition that eliminates
these features.
-->
50 <!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.
-->
55
<!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
60 -->
<!--============== Imported Names ==============================-->
<!ENTITY % Content-Type "CDATA"
65 -- meaning an internet media type
(aka MIME content type, as per RFC1521)
-->
<!ENTITY % HTTP-Method "GET | POST"
70 -- as per HTTP specification, in progress
-->
<!ENTITY % URI "CDATA"
-- The term URI means a CDATA attribute
75 whose value is a Uniform Resource Identifier,
as defined by
"Universal Resource Identifiers" by Tim Berners-Lee
aka RFC 1630
80 Note that CDATA attributes are limited by the LITLEN
capacity (1024 in the current version of html.decl),
so that URIs in HTML have a bounded length.
-->
85
<!--========= DTD "Macros" =====================-->
<!ENTITY % heading "H1|H2|H3|H4|H5|H6">
90
<!ENTITY % list " UL | OL | DIR | MENU " >
<!--======= Character mnemonic entities =================-->
95
<!ENTITY % ISOlat1 PUBLIC
"ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML">
%ISOlat1;
100 <!ENTITY amp CDATA "&" -- ampersand -->
<!ENTITY gt CDATA ">" -- greater than -->
<!ENTITY lt CDATA "<" -- less than -->
<!ENTITY quot CDATA """ -- double quote -->
105
<!--========= 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
110 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
115 SDA & ICADD:
- ISO 12083:1993, Annex A.8, Facilities for Braille,
large print and computer voice
- ICADD ListServ
<ICADD%ASUACAD.BITNET@ARIZVM1.ccit.arizona.edu>
120 - Usenet news group bit.listserv.easi
- Recording for the Blind, +1 800 221 4792
-->
<!ENTITY % SDAFORM "SDAFORM CDATA #FIXED"
125 -- one to one mapping -->
<!ENTITY % SDARULE "SDARULE CDATA #FIXED"
-- context-sensitive mapping -->
<!ENTITY % SDAPREF "SDAPREF CDATA #FIXED"
-- generated text prefix -->
130 <!ENTITY % SDASUFF "SDASUFF CDATA #FIXED"
-- generated text suffix -->
<!ENTITY % SDASUSP "SDASUSP NAME #FIXED"
-- suspend transform process -->
135
<!--========== Text Markup =====================-->
<![ %HTML.Highlighting [
140 <!ENTITY % font " TT | B | I ">
<!ENTITY % phrase "EM | STRONG | CODE | SAMP | KBD | VAR | CITE ">
<!ENTITY % text "#PCDATA | A | IMG | BR | %phrase | %font">
145
<!ELEMENT (%font;|%phrase) - - (%text)*>
<!ATTLIST ( TT | CODE | SAMP | KBD | VAR )
%SDAFORM; "Lit"
>
150 <!ATTLIST ( B | STRONG )
%SDAFORM; "B"
>
<!ATTLIST ( I | EM | CITE )
%SDAFORM; "It"
155 >
<!-- <TT> Typewriter text -->
<!-- <B> Bold text -->
<!-- <I> Italic text -->
160
<!-- <EM> Emphasized phrase -->
<!-- <STRONG> Strong emphais -->
<!-- <CODE> Source code phrase -->
<!-- <SAMP> Sample text or characters -->
165 <!-- <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">
170
]]>
<!ENTITY % text "#PCDATA | A | IMG | BR">
175 <!ELEMENT BR - O EMPTY>
<!ATTLIST BR
%SDAPREF; "&#RE;"
>
180 <!-- <BR> Line break -->
<!--========= Link Markup ======================-->
185 <![ %HTML.Recommended [
<!ENTITY % linkName "ID">
]]>
<!ENTITY % linkName "CDATA">
190
<!ENTITY % linkType "NAME"
-- a list of these will be specified at a later date -->
<!ENTITY % linkExtraAttributes
195 "REL %linkType #IMPLIED
REV %linkType #IMPLIED
URN CDATA #IMPLIED
TITLE CDATA #IMPLIED
METHODS NAMES #IMPLIED
200 ">
<![ %HTML.Recommended [
<!ENTITY % A.content "(%text)*"
-- <H1><a name="xxx">Heading</a></H1>
205 is preferred to
<a name="xxx"><H1>Heading</H1></a>
-->
]]>
210 <!ENTITY % A.content "(%heading|%text)*">
<!ELEMENT A - - %A.content -(A)>
<!ATTLIST A
HREF %URI #IMPLIED
215 NAME %linkName #IMPLIED
%linkExtraAttributes;
%SDAPREF; "<Anchor: #AttList>"
>
<!-- <A> Anchor; source/destination of link -->
220 <!-- <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 -->
225 <!-- <A TITLE="..."> Title of destination (advisory) -->
<!-- <A METHODS="..."> Operations on destination (advisory) -->
<!--========== Images ==========================-->
230
<!ELEMENT IMG - O EMPTY>
<!ATTLIST IMG
SRC %URI; #REQUIRED
ALT CDATA #IMPLIED
235 ALIGN (top|middle|bottom) #IMPLIED
ISMAP (ISMAP) #IMPLIED
%SDAPREF; "<Fig><?SDATrans Img: #AttList>#AttVal(Alt)</Fig>"
>
240 <!-- <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 -->
245
<!--========== Paragraphs=======================-->
<!ELEMENT P - O (%text)*>
<!ATTLIST P
250 %SDAFORM; "Para"
>
<!-- <P> Paragraph -->
255
<!--========== Headings, Titles, Sections ===============-->
<!ELEMENT HR - O EMPTY>
<!ATTLIST HR
260 %SDAPREF; "&#RE;&#RE;"
>
<!-- <HR> Horizontal rule -->
265 <!ELEMENT ( %heading ) - - (%text;)*>
<!ATTLIST H1
%SDAFORM; "H1"
>
<!ATTLIST H2
270 %SDAFORM; "H2"
>
<!ATTLIST H3
%SDAFORM; "H3"
>
275 <!ATTLIST H4
%SDAFORM; "H4"
>
<!ATTLIST H5
%SDAFORM; "H5"
280 >
<!ATTLIST H6
%SDAFORM; "H6"
>
285 <!-- <H1> Heading, level 1 -->
<!-- <H2> Heading, level 2 -->
<!-- <H3> Heading, level 3 -->
<!-- <H4> Heading, level 4 -->
<!-- <H5> Heading, level 5 -->
290 <!-- <H6> Heading, level 6 -->
<!--========== Text Flows ======================-->
295 <![ %HTML.Forms [
<!ENTITY % block.forms "BLOCKQUOTE | FORM | ISINDEX">
]]>
<!ENTITY % block.forms "BLOCKQUOTE">
300
<![ %HTML.Deprecated [
<!ENTITY % preformatted "PRE | XMP | LISTING">
]]>
305 <!ENTITY % preformatted "PRE">
<!ENTITY % block "P | %list | DL
| %preformatted
| %block.forms">
310
<!ENTITY % flow "(%text|%block)*">
<!ENTITY % pre.content "#PCDATA | A | HR | BR">
<!ELEMENT PRE - - (%pre.content)*>
315 <!ATTLIST PRE
WIDTH NUMBER #implied
%SDAFORM; "Lit"
>
320 <!-- <PRE> Preformatted text -->
<!-- <PRE WIDTH=...> Maximum characters per line -->
<![ %HTML.Deprecated [
325 <!ENTITY % literal "CDATA"
-- historical, non-conforming parsing mode where
the only markup signal is the end tag
in full
-->
330
<!ELEMENT (XMP|LISTING) - - %literal>
<!ATTLIST XMP
%SDAFORM; "Lit"
%SDAPREF; "Example:&#RE;"
335 >
<!ATTLIST LISTING
%SDAFORM; "Lit"
%SDAPREF; "Listing:&#RE;"
>
340
<!-- <XMP> Example section -->
<!-- <LISTING> Computer listing -->
<!ELEMENT PLAINTEXT - O %literal>
345 <!-- <PLAINTEXT> Plain text passage -->
<!ATTLIST PLAINTEXT
%SDAFORM; "Lit"
>
350 ]]>
<!--========== Lists ==================-->
355 <!ELEMENT DL - - (DT | DD)+>
<!ATTLIST DL
COMPACT (COMPACT) #IMPLIED
%SDAFORM; "List"
%SDAPREF; "Definition List:"
360 >
<!ELEMENT DT - O (%text)*>
<!ATTLIST DT
%SDAFORM; "Term"
365 >
<!ELEMENT DD - O %flow>
<!ATTLIST DD
%SDAFORM; "LItem"
370 >
<!-- <DL> Definition list, or glossary -->
<!-- <DL COMPACT> Compact style list -->
<!-- <DT> Term in definition list -->
375 <!-- <DD> Definition of term -->
<!ELEMENT (OL|UL) - - (LI)+>
<!ATTLIST OL
COMPACT (COMPACT) #IMPLIED
380 %SDAFORM; "List"
>
<!ATTLIST UL
COMPACT (COMPACT) #IMPLIED
%SDAFORM; "List"
385 >
<!-- <UL> Unordered list -->
<!-- <UL COMPACT> Compact list style -->
<!-- <OL> Ordered, or numbered list -->
<!-- <OL COMPACT> Compact list style -->
390
<!ELEMENT (DIR|MENU) - - (LI)+ -(%block)>
<!ATTLIST DIR
COMPACT (COMPACT) #IMPLIED
395 %SDAFORM; "List"
%SDAPREF; "<LHead>Directory</LHead>"
>
<!ATTLIST MENU
COMPACT (COMPACT) #IMPLIED
400 %SDAFORM; "List"
%SDAPREF; "<LHead>Menu</LHead>"
>
<!-- <DIR> Directory list -->
405 <!-- <DIR COMPACT> Compact list style -->
<!-- <MENU> Menu list -->
<!-- <MENU COMPACT> Compact list style -->
<!ELEMENT LI - O %flow>
410 <!ATTLIST LI
%SDAFORM; "LItem"
>
<!-- <LI> List item -->
415
<!--========== Document Body ===================-->
<![ %HTML.Recommended [
<!ENTITY % body.content "(%heading|%block|HR|ADDRESS|IMG)*"
420 -- <h1>Heading</h1>
<p>Text ...
is preferred to
<h1>Heading</h1>
Text ...
425 -->
]]>
<!ENTITY % body.content "(%heading | %text | %block |
HR | ADDRESS)*">
430
<!ELEMENT BODY O O %body.content>
<!-- <BODY> Document body -->
435 <!ELEMENT BLOCKQUOTE - - %body.content>
<!ATTLIST BLOCKQUOTE
%SDAFORM; "BQ"
>
440 <!-- <BLOCKQUOTE> Quoted passage -->
<!ELEMENT ADDRESS - - (%text|P)*>
<!ATTLIST ADDRESS
%SDAFORM; "Lit"
445 %SDAPREF; "Address:&#RE;"
>
<!-- <ADDRESS> Address, signature, or byline -->
450
<!--======= Forms ====================-->
<![ %HTML.Forms [
455 <!ELEMENT FORM - - %body.content -(FORM) +(INPUT|SELECT|TEXTAREA)>
<!ATTLIST FORM
ACTION %URI #IMPLIED
METHOD (%HTTP-Method) GET
ENCTYPE %Content-Type; "application/x-www-form-urlencoded"
460 %SDAPREF; "<Para>Form:</Para>"
%SDASUFF; "<Para>Form End.</Para>"
>
<!-- <FORM> Fill-out or data-entry form -->
465 <!-- <FORM ACTION="..."> Address for completed form -->
<!-- <FORM METHOD=...> Method of submitting form -->
<!-- <FORM ENCTYPE="..."> Representation of form data -->
<!ENTITY % InputType "(TEXT | PASSWORD | CHECKBOX |
470 RADIO | SUBMIT | RESET |
IMAGE | HIDDEN )">
<!ELEMENT INPUT - O EMPTY>
<!ATTLIST INPUT
TYPE %InputType TEXT
475 NAME CDATA #IMPLIED
VALUE CDATA #IMPLIED
SRC %URI #IMPLIED
CHECKED (CHECKED) #IMPLIED
SIZE CDATA #IMPLIED
480 MAXLENGTH NUMBER #IMPLIED
ALIGN (top|middle|bottom) #IMPLIED
%SDAPREF; "Input: "
>
485 <!-- <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 -->
490 <!-- <INPUT CHECKED> Initial state is "on" -->
<!-- <INPUT SIZE=...> Field size hint -->
<!-- <INPUT MAXLENGTH=...> Data length maximum -->
<!-- <INPUT ALIGN=...> Image alignment -->
495 <!ELEMENT SELECT - - (OPTION+) -(INPUT|SELECT|TEXTAREA)>
<!ATTLIST SELECT
NAME CDATA #REQUIRED
SIZE NUMBER #IMPLIED
MULTIPLE (MULTIPLE) #IMPLIED
500 %SDAFORM; "List"
%SDAPREF;
"<LHead>Select #AttVal(Multiple)</LHead>"
>
505 <!-- <SELECT> Selection of option(s) -->
<!-- <SELECT NAME=...> Name of form datum -->
<!-- <SELECT SIZE=...> Options displayed at a time -->
<!-- <SELECT MULTIPLE> Multiple selections allowed -->
510 <!ELEMENT OPTION - O (#PCDATA)*>
<!ATTLIST OPTION
SELECTED (SELECTED) #IMPLIED
VALUE CDATA #IMPLIED
%SDAFORM; "LItem"
515 %SDAPREF;
"Option: #AttVal(Value) #AttVal(Selected)"
>
<!-- <OPTION> A selection option -->
520 <!-- <OPTION SELECTED> Initial state -->
<!-- <OPTION VALUE="..."> Form datum value for this option-->
<!ELEMENT TEXTAREA - - (#PCDATA)* -(INPUT|SELECT|TEXTAREA)>
<!ATTLIST TEXTAREA
525 NAME CDATA #REQUIRED
ROWS NUMBER #REQUIRED
COLS NUMBER #REQUIRED
%SDAFORM; "Para"
%SDAPREF; "Input Text -- #AttVal(Name): "
530 >
<!-- <TEXTAREA> An area for text input -->
<!-- <TEXTAREA NAME=...> Name of form datum -->
<!-- <TEXTAREA ROWS=...> Height of area -->
535 <!-- <TEXTAREA COLS=...> Width of area -->
]]>
540 <!--======= Document Head ======================-->
<![ %HTML.Recommended [
<!ENTITY % head.extra "META* & LINK*">
]]>
545
<!ENTITY % head.extra "NEXTID? & META* & LINK*">
<!ENTITY % head.content "TITLE & ISINDEX? & BASE? &
(%head.extra)">
550
<!ELEMENT HEAD O O (%head.content)>
<!-- <HEAD> Document head -->
555 <!ELEMENT TITLE - - (#PCDATA)*>
<!ATTLIST TITLE
%SDAFORM; "Ti" >
<!-- <TITLE> Title of document -->
560
<!ELEMENT LINK - O EMPTY>
<!ATTLIST LINK
HREF %URI #REQUIRED
%linkExtraAttributes;
565 %SDAPREF; "Linked to : #AttVal (TITLE) (URN) (HREF)>" >
<!-- <LINK> Link from this document -->
<!-- <LINK HREF="..."> Address of link destination -->
<!-- <LINK URN="..."> Lasting name of destination -->
570 <!-- <LINK REL=...> Relationship to destination -->
<!-- <LINK REV=...> Relationship of destination to this -->
<!-- <LINK TITLE="..."> Title of destination (advisory) -->
<!-- <LINK METHODS="..."> Operations allowed (advisory) -->
575 <!ELEMENT ISINDEX - O EMPTY>
<!ATTLIST ISINDEX
%SDAPREF;
"<Para>[Document is indexed/searchable.]</Para>">
580 <!-- <ISINDEX> Document is a searchable index -->
<!ELEMENT BASE - O EMPTY>
<!ATTLIST BASE
HREF %URI; #REQUIRED >
585
<!-- <BASE> Base context document -->
<!-- <BASE HREF="..."> Address for this document -->
<!ELEMENT NEXTID - O EMPTY>
590 <!ATTLIST NEXTID
N %linkName #REQUIRED >
<!-- <NEXTID> Next ID to use for link name -->
<!-- <NEXTID N=...> Next ID to use for link name -->
595
<!ELEMENT META - O EMPTY>
<!ATTLIST META
HTTP-EQUIV NAME #IMPLIED
NAME NAME #IMPLIED
600 CONTENT CDATA #REQUIRED >
<!-- <META> Generic Metainformation -->
<!-- <META HTTP-EQUIV=...> HTTP response header name -->
<!-- <META NAME=...> Metainformation name -->
605 <!-- <META CONTENT="..."> Associated information -->
<!--======= Document Structure =================-->
<![ %HTML.Deprecated [
610 <!ENTITY % html.content "HEAD, BODY, PLAINTEXT?">
]]>
<!ENTITY % html.content "HEAD, BODY">
<!ELEMENT HTML O O (%html.content)>
615 <!ENTITY % version.attr "VERSION CDATA #FIXED '%HTML.Version;'">
<!ATTLIST HTML
%version.attr;
%SDAFORM; "Book"
620 >
<!-- <HTML> HTML Document -->
11.2. SGML Declaration for HTML
This is the SGML Declaration for HyperText Markup Language
(HTML) as used by the World Wide Web (WWW) application:
<!SGML "ISO 8879:1986"
--
SGML Declaration for HyperText Markup Language (HTML).
5 --
CHARSET
BASESET "ISO 646:1983//CHARSET
International Reference Version
10 (IRV)//ESC 2/5 4/0"
DESCSET 0 9 UNUSED
9 2 9
11 2 UNUSED
13 1 13
15 14 18 UNUSED
32 95 32
127 1 UNUSED
BASESET "ISO Registration Number 100//CHARSET
ECMA-94 Right Part of
20 Latin Alphabet Nr. 1//ESC 2/13 4/1"
DESCSET 128 32 UNUSED
160 96 32
25 CAPACITY SGMLREF
TOTALCAP 150000
GRPCAP 150000
ENTCAP 150000
30 SCOPE DOCUMENT
SYNTAX
SHUNCHAR CONTROLS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 127
BASESET "ISO 646:1983//CHARSET
35 International Reference Version
(IRV)//ESC 2/5 4/0"
DESCSET 0 128 0
FUNCTION
RE 13
40 RS 10
SPACE 32
TAB SEPCHAR 9
45 NAMING LCNMSTRT ""
UCNMSTRT ""
LCNMCHAR ".-"
UCNMCHAR ".-"
NAMECASE GENERAL YES
50 ENTITY NO
DELIM GENERAL SGMLREF
SHORTREF SGMLREF
NAMES SGMLREF
QUANTITY SGMLREF
55 ATTSPLEN 2100
LITLEN 1024
NAMELEN 72 -- somewhat arbitrary; taken from
internet line length conventions --
PILEN 1024
60 TAGLEN 2100
GRPGTCNT 150
GRPCNT 64
FEATURES
65 MINIMIZE
DATATAG NO
OMITTAG YES
RANK NO
SHORTTAG YES
70 LINK
SIMPLE NO
IMPLICIT NO
EXPLICIT NO
OTHER
75 CONCUR NO
SUBDOC NO
FORMAL YES
APPINFO "SDA" -- conforming SGML Document Access application
--
80 >
<!--
$Id: html.decl,v 1.15 1995/05/06 01:44:47 connolly Exp $
Author: Daniel W. Connolly <connolly@hal.com>
85
See also: http://www.hal.com/%7Econnolly/html-spec
http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html
-->
11.3. 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 indentifier. 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 --
5 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
10 -- 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 --
15 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 specific \
& --
20 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
25 -- Ways to refer to Strict Level 1: most general to most specific \
& --
PUBLIC "-//IETF//DTD HTML Strict Level 1//EN" html-1s.dtd
PUBLIC "-//IETF//DTD HTML 2.0 Strict Level 1//EN" html-1s.dtd
-- Ways to refer to Strict Level 0: most general to most specific \
& --
30 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.sg\
& ml
11.4. 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.
11.4.1. 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 < Less than sign
> gt > Greater than sign
& amp & Ampersand
" quot " Double quote sign
11.4.2. 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.
5 -->
<!-- Character entity set. Typical invocation:
<!ENTITY % ISOlat1 PUBLIC
"ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML">
%ISOlat1;
10 -->
<!-- Modified for use in HTML
$Id: ISOlat1.sgml,v 1.2 1994/11/30 23:45:12 connolly Exp $ -->
<!ENTITY AElig CDATA "Æ" -- capital AE diphthong (ligature) -->
<!ENTITY Aacute CDATA "Á" -- capital A, acute accent -->
15 <!ENTITY Acirc CDATA "Â" -- capital A, circumflex accent -->
<!ENTITY Agrave CDATA "À" -- capital A, grave accent -->
<!ENTITY Aring CDATA "Å" -- capital A, ring -->
<!ENTITY Atilde CDATA "Ã" -- capital A, tilde -->
<!ENTITY Auml CDATA "Ä" -- capital A, dieresis or umlaut mark -->
20 <!ENTITY Ccedil CDATA "Ç" -- capital C, cedilla -->
<!ENTITY ETH CDATA "Ð" -- capital Eth, Icelandic -->
<!ENTITY Eacute CDATA "É" -- capital E, acute accent -->
<!ENTITY Ecirc CDATA "Ê" -- capital E, circumflex accent -->
<!ENTITY Egrave CDATA "È" -- capital E, grave accent -->
25 <!ENTITY Euml CDATA "Ë" -- capital E, dieresis or umlaut mark -->
<!ENTITY Iacute CDATA "Í" -- capital I, acute accent -->
<!ENTITY Icirc CDATA "Î" -- capital I, circumflex accent -->
<!ENTITY Igrave CDATA "Ì" -- capital I, grave accent -->
<!ENTITY Iuml CDATA "Ï" -- capital I, dieresis or umlaut mark -->
30 <!ENTITY Ntilde CDATA "Ñ" -- capital N, tilde -->
<!ENTITY Oacute CDATA "Ó" -- capital O, acute accent -->
<!ENTITY Ocirc CDATA "Ô" -- capital O, circumflex accent -->
<!ENTITY Ograve CDATA "Ò" -- capital O, grave accent -->
<!ENTITY Oslash CDATA "Ø" -- capital O, slash -->
35 <!ENTITY Otilde CDATA "Õ" -- capital O, tilde -->
<!ENTITY Ouml CDATA "Ö" -- capital O, dieresis or umlaut mark -->
<!ENTITY THORN CDATA "Þ" -- capital THORN, Icelandic -->
<!ENTITY Uacute CDATA "Ú" -- capital U, acute accent -->
<!ENTITY Ucirc CDATA "Û" -- capital U, circumflex accent -->
40 <!ENTITY Ugrave CDATA "Ù" -- capital U, grave accent -->
<!ENTITY Uuml CDATA "Ü" -- capital U, dieresis or umlaut mark -->
<!ENTITY Yacute CDATA "Ý" -- capital Y, acute accent -->
<!ENTITY aacute CDATA "á" -- small a, acute accent -->
<!ENTITY acirc CDATA "â" -- small a, circumflex accent -->
45 <!ENTITY aelig CDATA "æ" -- small ae diphthong (ligature) -->
<!ENTITY agrave CDATA "à" -- small a, grave accent -->
<!ENTITY aring CDATA "å" -- small a, ring -->
<!ENTITY atilde CDATA "ã" -- small a, tilde -->
<!ENTITY auml CDATA "ä" -- small a, dieresis or umlaut mark -->
50 <!ENTITY ccedil CDATA "ç" -- small c, cedilla -->
<!ENTITY eacute CDATA "é" -- small e, acute accent -->
<!ENTITY ecirc CDATA "ê" -- small e, circumflex accent -->
<!ENTITY egrave CDATA "è" -- small e, grave accent -->
<!ENTITY eth CDATA "ð" -- small eth, Icelandic -->
55 <!ENTITY euml CDATA "ë" -- small e, dieresis or umlaut mark -->
<!ENTITY iacute CDATA "í" -- small i, acute accent -->
<!ENTITY icirc CDATA "î" -- small i, circumflex accent -->
<!ENTITY igrave CDATA "ì" -- small i, grave accent -->
<!ENTITY iuml CDATA "ï" -- small i, dieresis or umlaut mark -->
60 <!ENTITY ntilde CDATA "ñ" -- small n, tilde -->
<!ENTITY oacute CDATA "ó" -- small o, acute accent -->
<!ENTITY ocirc CDATA "ô" -- small o, circumflex accent -->
<!ENTITY ograve CDATA "ò" -- small o, grave accent -->
<!ENTITY oslash CDATA "ø" -- small o, slash -->
65 <!ENTITY otilde CDATA "õ" -- small o, tilde -->
<!ENTITY ouml CDATA "ö" -- small o, dieresis or umlaut mark -->
<!ENTITY szlig CDATA "ß" -- small sharp s, German (sz ligature) -->
<!ENTITY thorn CDATA "þ" -- small thorn, Icelandic -->
<!ENTITY uacute CDATA "ú" -- small u, acute accent -->
70 <!ENTITY ucirc CDATA "û" -- small u, circumflex accent -->
<!ENTITY ugrave CDATA "ù" -- small u, grave accent -->
<!ENTITY uuml CDATA "ü" -- small u, dieresis or umlaut mark -->
<!ENTITY yacute CDATA "ý" -- small y, acute accent -->
<!ENTITY yuml CDATA "ÿ" -- small y, dieresis or umlaut mark -->
12. Glossary
character
An atom of information, for example a letter or a
digit. Graphic characters have associated glyphs,
where as 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; version=2.0'.
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, sually
a start-tag and end-tag. [SGML]
end-tag
Descriptive markup that identifies the end of an
element. [SGML]
entity
data with an associated notation or
interpretation; for example, a sequence of octets
associated with an Internet Media Type.[SGML]
HTML document
An SGML document conforming to this document type
definition.
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.
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]
must
Documents or user agents in conflict with this
statement are not conforming.
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 Universal Resource Identifier is a formatted
string that serves as an identifier for a
resource, typcally on the Internet. URIs are used
in HTML to identify the destination of hypertext
links, the source of in-line images, and the
object of form actions. URIs in common use 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. Users may
create, edit or browse hypertext documents.
`http://www.w3.org/'
13. Bibliography
[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]
T. Berners-Lee, L. Masinter, and M. McCahill.
``Uniform Resource Locators (URL).'' RFC 1738,
CERN, Xerox PARC, University of Minnesota, October
1994.
[HTTP]
T. Berners-Lee, R. T. Fielding, and H. Frystyk
Nielsen. ``Hypertext Transfer Protocol -
HTTP/1.0.'' Work in Progress
(draft-ietf-http-v10-spec-00.ps), MIT, UC Irvine,
CERN, March 1995.
[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.
[RELURL]
R. T. Fielding. ``Relative Uniform Resource
Locators.'' Work in Progress (draft-ietf-uri-
relative-url-06.txt), UC Irvine, March 1995.
[GOLD90]
C. F. Goldfarb. ``The SGML Handbook.'' Y.
Rubinsky, Ed., Oxford University Press, 1990.
[IMEDIA]
J. Postel. ``Media Type Registration Procedure.''
RFC 1590, USC/ISI, March 1994.
[IANA]
J. Reynolds and J. Postel. ``Assigned Numbers.''
STD 2, RFC 1700, USC/ISI, October 1994.
[SQ91]
SoftQuad. ``The SGML Primer.'' 3rd ed., SoftQuad
Inc., 1991.
[US-ASCII]
US-ASCII. Coded Character Set - 7-Bit American
Standard Code for Information Interchange.
Standard ANSI X3.4-1986, ANSI, 1986.
[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. Part 2: Latin alphabet No. 2, ISO
8859-2, 1987. Part 3: Latin alphabet No. 3, ISO
8859-3, 1988. Part 4: Latin alphabet No. 4, ISO
8859-4, 1988. Part 5: Latin/Cyrillic alphabet, ISO
8859-5, 1988. Part 6: Latin/Arabic alphabet, ISO
8859-6, 1987. Part 7: Latin/Greek alphabet, ISO
8859-7, 1987. Part 8: Latin/Hebrew alphabet, ISO
8859-8, 1988. Part 9: Latin alphabet No. 5, ISO
8859-9, 1990.
[SGML]
ISO 8879. Information Processing - Text and Office
Systems - Standard Generalized Markup Language
(SGML), 1986.
14. Appendices
These appendices are provided for informational reasons only
- they do not form a part of the HTML specification.
14.1. The ISO-8859-1 Coded Character Set
This list, sorted numerically, is derived from ISO-8859-1
8-bit single-byte coded graphic character set:
REFERENCE DESCRIPTION
� -  Unused
	 Horizontal tab
Line feed
 -  Unused
  Space
! Exclamation mark
" Quotation mark
# Number sign
$ Dollar sign
% Percent sign
& Ampersand
' Apostrophe
( Left parenthesis
) Right parenthesis
* Asterisk
+ Plus sign
, Comma
- Hyphen
. Period (fullstop)
/ Solidus (slash)
0 - 9 Digits 0-9
: Colon
; Semi-colon
< Less than
= Equals sign
> Greater than
? Question mark
@ Commercial at
A - Z Letters A-Z
[ Left square bracket
\ Reverse solidus (backslash)
] Right square bracket
^ Caret
_ Horizontal bar (underscore)
` Acute accent
a - z Letters a-z
{ Left curly brace
| Vertical bar
} Right curly brace
~ Tilde
 -   Unused
¡ Inverted exclamation
¢ Cent sign
£ Pound sterling
¤ General currency sign
¥ Yen sign
¦ Broken vertical bar
§ Section sign
¨ Umlaut (dieresis)
© Copyright
ª Feminine ordinal
« Left angle quote, guillemotleft
¬ Not sign
­ Soft hyphen
® Registered trademark
¯ Macron accent
° Degree sign
± Plus or minus
² Superscript two
³ Superscript three
´ Acute accent
µ Micro sign
¶ Paragraph sign
· Middle dot
¸ Cedilla
¹ Superscript one
º Masculine ordinal
» Right angle quote, guillemotright
¼ Fraction one-fourth
½ Fraction one-half
¾ Fraction three-fourths
¿ Inverted question mark
À Capital A, grave accent
Á Capital A, acute accent
 Capital A, circumflex accent
à Capital A, tilde
Ä Capital A, dieresis or umlaut mark
Å Capital A, ring
Æ Capital AE dipthong (ligature)
Ç Capital C, cedilla
È Capital E, grave accent
É Capital E, acute accent
Ê Capital E, circumflex accent
Ë Capital E, dieresis or umlaut mark
Ì Capital I, grave accent
Í Capital I, acute accent
Î Capital I, circumflex accent
Ï Capital I, dieresis or umlaut mark
Ð Capital Eth, Icelandic
Ñ Capital N, tilde
Ò Capital O, grave accent
Ó Capital O, acute accent
Ô Capital O, circumflex accent
Õ Capital O, tilde
Ö Capital O, dieresis or umlaut mark
× Multiply sign
Ø Capital O, slash
Ù Capital U, grave accent
Ú Capital U, acute accent
Û Capital U, circumflex accent
Ü Capital U, dieresis or umlaut mark
Ý Capital Y, acute accent
Þ Capital THORN, Icelandic
ß Small sharp s, German (sz ligature)
à Small a, grave accent
á Small a, acute accent
â Small a, circumflex accent
ã Small a, tilde
ä Small a, dieresis or umlaut mark
å Small a, ring
æ Small ae dipthong (ligature)
ç Small c, cedilla
è Small e, grave accent
é Small e, acute accent
ê Small e, circumflex accent
ë Small e, dieresis or umlaut mark
ì Small i, grave accent
í Small i, acute accent
î Small i, circumflex accent
ï Small i, dieresis or umlaut mark
ð Small eth, Icelandic
ñ Small n, tilde
ò Small o, grave accent
ó Small o, acute accent
ô Small o, circumflex accent
õ Small o, tilde
ö Small o, dieresis or umlaut mark
÷ Division sign
ø Small o, slash
ù Small u, grave accent
ú Small u, acute accent
û Small u, circumflex accent
ü Small u, dieresis or umlaut mark
ý Small y, acute accent
þ Small thorn, Icelandic
ÿ Small y, dieresis or umlaut mark
14.2. Obsolete Features
This section describes elements that are no longer part of
HTML. Client implementors should implement these obsolete
elements for compatibility with previous versions of the
HTML specification.
14.2.1. Comment Element
The Comment element is used to delimit unneeded text and
comments. The Comment element has been introduced in some
HTML applications but should be replaced by the SGML comment
feature in new HTML interpreters (see Section 2.2.5).
14.2.2. Highlighted Phrase Element
<HP>
The Highlighted Phrase element should be ignored if not
implemented. This element has been replaced by more
meaningful elements (see Section 8).
Example of use:
<HP1>first highlighted phrase</HP1>non-
highlighted text<HP2>second highlighted phrase</HP2> etc.
14.2.3. Plain Text Element
<PLAINTEXT>
The Plain Text element is used to terminates the HTML entity
and to indicate that what follows is not SGML which does not
require parsing. Instead, an old HTTP convention specified
that what followed was an ASCII (MIME ``text/plain'') body.
Its presence is an optimization. There is no closing tag.
Example of use:
<PLAINTEXT>
0001 This is line one of a long listing
0002 file from <ANY@HOST.INC.COM> which is sent
14.2.4. Example and Listing Elements
<XMP> ... </XMP> and <LISTING> ... </LISTING>
The Example and Listing elements have been replaced by the
Preformatted Text element (Section 10.2).
These styles allow text of fixed-width characters to be
embedded absolutely as is into the document. The syntax is:
<LISTING> ... </LISTING>
or
<XMP> ... </XMP>
The text between these tags is typically rendered in a
monospaced font so that any formatting done by character
spacing on successive lines will be maintained.
Between the opening and closing tags:
* The text may contain any ISO Latin-1 printable
characters, except for the end-tag opener. The Example
and Listing elements have historically used
specifications which do not conform to SGML.
Specifically, the text may contain ISO Latin printable
characters, including the tag opener, as long it they
does not contain the closing tag in full.
* SGML does not support this form. HTML interpreters
may vary on how they interpret other tags within
Example and Listing elements.
* Line boundaries within the text are rendered as a
move to the beginning of the next line, except for one
immediately following a start-tag or immediately
preceding an end-tag.
* The horizontal tab character 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. Its use is not recommended.
The Listing element is rendered so that at least 132
characters fit on a line. The Example element is rendered to
that at least 80 characters fit on a line but is otherwise
identical to the Listing element.
14.3. Proposed Features
This section describes proposed HTML elements and entities
that are not currently supported under HTML Levels 0, 1, or
2@@, but may be supported in the future.
14.3.1. Additional Character Entities
To indicate special characters, HTML uses entity or numeric
representations. Additional character presentations are
proposed:
CHARACTER REPRESENTATION
Non-breaking space
Soft-hyphen ­
Registered ®
Copyright ©
14.3.2. Defining Instance Element
<DFN> ... </DFN>
The Defining Instance element indicates the defining
instance of a term. The typical rendering is bold or bold
italic. This element is not widely supported.
14.3.3. Strike Element
<STRIKE> ... </STRIKE>
The Strike element is proposed to indicate strikethrough, a
font style in which a horizontal line appears through
characters. This element is not widely supported.
14.3.4. Underline Element
<U> ... </U>
The Underline element is proposed to indicate that the text
should be rendered as underlined. This proposed tag is not
supported by all HTML interpreters.
Example of use:
The text <U>shown here</U> is rendered in the
document as underlined.
15. 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 people who have contributed to
this specification:
Terry Allen Marc Andreessen
Tim Berners-Lee Paul Burchard
James Clark Daniel W. Connolly
Roy T. Fielding Peter Flynn
Jay Glicksman Paul Grosso
Eduardo Gutentag Bill Hefley
Chung-Jen Ho Mike Knezovich
Tom Magliery Murray Maloney
Larry Masinter Karen Olson Muldrow
Bill Perry Dave Raggett
E. Corprew Reed Yuri Rubinsky
Eric Schieler James L. Seidman
Eric W. Sink Stuart Weibel
Chris Wilson Francois Yergeau
15.1. 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/
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