Background on HTML
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Hypertext
Markup Language.
HTML is a
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.
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The World Wide Web
a distributed hypertext-based information system developed at
CERN,
is a globally interconnected network of hypermedia information
based on
- the Internet
- A uniform addressing scheme for locating resources on the Web
(e.g., URLs).
- Protocols,
for access to named resources over the Web
(e.g., HTTP).
- Hypertext, for easy navigation among resources
(e.g.
HyperText Markup Language or HTML,
a standard format for describing the structure of documents
for transmission of hypermedia documents).
HTML documents are ASCII files with embedded codes for logical markup,
format
(text styles, document titles, paragraphs, tables) and hyperlinks.
- a set of
servers
that respond to requests from
- browsers
(or clients) for those documents.
WWW also interfaces with other
standard protocols (FTP, Telnet, NNTP,
WAIS, gopher, ...) and their data formats.
HTML 3.2 is W3C's current standard for HTML,
developed together with vendors including IBM, Microsoft,
Netscape Communications Corporation, Novell, SoftQuad,
Spyglass, and Sun Microsystems.
HTML 3.2 aims to capture recommended practice as of early '96
and as such to be used as a replacement for
HTML 2.0 (RFC 1866).
HTML 3.2 adds widely deployed features such as tables,
applets and text flow around images,
while providing backwards compatibility with the existing
standard HTML 2.0.
HTML 3.2 extends the existing
Internet Engineering Task Force (IETF)
standard HTML 2.0 with ideas from several sources.
The W3C's
Editorial Review Board (ERB) incorporated designs
from the
HTML+
and
HTML 3.0 proposals by
Dave Raggett.
The original HTML specification was written by
Tim Berners-Lee,
Director of
W3C, while he was at
CERN.
Innovations driven by the
National Center for Supercomputing
Applications (NCSA)
Mosaic
team and many other contributors
were incorporated by an IETF working group, leading to the
HTML 2.0 specification
(Request For Comments
#1866), edited by W3C Architecture Domain Leader
Dan Connolly.
The
W3C is continuing to work with vendors on extensions to future versions
of HTML for
multimedia objects,
scripting,
style sheets,
layout,
forms,
higher quality printing, and
math.
Along with the invention of a new scheme for
naming any Internet information resource
(URLs)
and a new protocol for sending files across the
Internet
(HTTP),
the Web needed a new data format for including links and
device-independent formatting to glue it all together.
HTML uses structural markup which emphasizes the meaning of a document:
"...This is the second item in a list; this is a top-level heading...".
It's completely up to the HTML processor how to format the document for
the recipient: as voice, as a text screen, as a graphical 'page', etc.
This power comes from HTML 3.2's conformance to International Standard
ISO 8879 -
Standard Generalized Markup Language.
Since the Web's hypertext documents are an
SGML application,
they are represented using text-based markup and are interoperable
across a wide range of platforms.
HTML 3.2 includes features for basic document idioms such as headings,
lists, paragraphs,
tables and images,
as well as hypertext links and electronic
fill-in forms.
HTML 3.2 documents are designed to be rendered in several ways:
on graphical displays, text-only displays, speech-based browsers,
and printed to hardcopy media.
Additional HTML 3.2 features support
meta-information describing link
relationships and document properties such as authorship,
content rating, and copyright statements.
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