HTML, which stands for HyperText Markup Language, is the predominant markup language for web pages. A markup language is a set of markup tags, and HTML uses markup tags to describe web pages.
HTML is written in the form of HTML elements consisting of "tags" surrounded by angle brackets (like <html>) within the web page content. HTML tags normally come in pairs like <b> and </b>. The first tag in a pair is the start tag, the second tag is the end tag (they are also called opening tags and closing tags).
The purpose of a web browser is to read HTML documents and display them as web pages. The browser does not display the HTML tags, but uses the tags to interpret the content of the page.
HTML elements form the building blocks of all websites. HTML allows images and objects to be embedded and can be used to create interactive forms. It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items. It can embed scripts in languages such as JavaScript which affect the behavior of HTML webpages.
HTML can also be used to include Cascading Style Sheets (CSS) to define the appearance and layout of text and other material. The W3C, maintainer of both HTML and CSS standards, encourages the use of CSS over explicit presentational markup.
History
Origins
In 1980, physicist Tim Berners-Lee, who was a contractor at CERN, proposed and prototyped ENQUIRE, a system for CERN researchers to use and share documents. In 1989, Berners-Lee wrote a memo proposing an Internet-based hypertext system.
Berners-Lee specified HTML and wrote the browser and server software in the last part of 1990. In that year, Berners-Lee and CERN data systems engineer Robert Cailliau collaborated on a joint request for funding, but the project was not formally adopted by CERN. In his personal notes
from 1990 he lists
"
some of the many areas in which hypertext is used" and puts an encyclopedia first.
HTML version timeline
November 24, 1995
HTML 2.0 was published as IETF RFC 1866. Supplemental RFCs added capabilities:
* November 25, 1995: RFC 1867 (form-based file upload)
* May 1996: RFC 1942 (tables)
* August 1996: RFC 1980 (client-side image maps)
* January 1997: RFC 2070 (internationalization)
In June 2000, all of these were declared obsolete/historic by RFC 2854.. | January 1997
HTML 3.2 was published as a W3C Recommendation. It was the first version developed and standardized exclusively by the W3C, as the IETF had closed its HTML Working Group in September 1996.
HTML 3.2 dropped math formulas entirely, reconciled overlap among various proprietary extensions and adopted most of Netscape's visual markup tags. Netscape's blink element and Microsoft's marquee element were omitted due to a mutual agreement between the two companies. A markup for mathematical formulas similar to that in HTML wasn't standardized until 14 months later in MathML.. |
December 1997
HTML 4.0 was published as a W3C Recommendation. It offers three variations:
* Strict, in which deprecated elements are forbidden,
* Transitional, in which deprecated elements are allowed,
* Frameset, in which mostly only frame related elements are allowed;
Initially code-named "Cougar",HTML 4.0 adopted many browser-specific element types and attributes, but at the same time sought to phase out Netscape's visual markup features by marking them as deprecated in favor of style sheets. HTML 4 is an SGML application conforming to ISO 8879 - SGML.. | April 1998
HTML 4.0 was reissued with minor edits without incrementing the version number.
December 1999
HTML 4.01 was published as a W3C Recommendation. It offers the same three variations as HTML 4.0 and its last errata were published May 12, 2001.. | May 2000
ISO/IEC 15445:2000 ("ISO HTML", based on HTML 4.01 Strict) was published as an ISO/IEC international standard. In the ISO this standard falls in the domain of the ISO/IEC JTC1/SC34 (ISO/IEC Joint Technical Committee 1, Subcommittee 34 - Document description and processing languages).
As of mid-2008, HTML 4.01 and ISO/IEC 15445:2000 are the most recent versions of HTML. Development of the parallel, XML-based language XHTML occupied the W3C's HTML Working Group through the early and mid-2000s.. |
HTML Draft Version Timeline
October 1991
HTML Tags, an informal CERN document listing twelve HTML tags, was first mentioned in public.
June 1992
First informal draft of the HTML DTD, with seven subsequent revisions (July 15, August 6, August 18, November 17, November 19, November 20, November 22)
November 1992
HTML DTD 1.1 (the first with a version number, based on RCS revisions, which start with 1.1 rather than 1.0), an informal draft
June 1993
Hypertext Markup Language was published by the IETF IIIR Working Group as an Internet-Draft (a rough proposal for a standard). It was replaced by a second version one month later, followed by six further drafts published by IETF itself that finally led to HTML 2.0 in RFC1866. | November 1993
HTML+ was published by the IETF as an Internet-Draft and was a competing proposal to the Hypertext Markup Language draft. It expired in May 1994.
April 1995 (authored March 1995)
HTML 3.0 was proposed as a standard to the IETF, but the proposal expired five months later without further action. It included many of the capabilities that were in Raggett's HTML+ proposal, such as support for tables, text flow around figures and the display of complex mathematical formulas.
W3C began development of its own Arena browser as a test bed for HTML 3 and Cascading Style Sheets,but HTML 3.0 did not succeed for several reasons. The draft was considered very large at 150 pages and the pace of browser development, as well as the number of interested parties, had outstripped the resources of the IET. Browser vendors, including Microsoft and Netscape at the time, chose to implement different subsets of HTML 3's draft features as well as to introduce their own extensions to it.These included extensions to control stylistic aspects of documents, contrary to the "belief [of the academic engineering community] that such things as text color, background texture, font size and font face were definitely outside the scope of a language when their only intent was to specify how a document would be organized. Dave Raggett, who has been a W3C Fellow for many years has commented for example, "To a certain extent, Microsoft built its business on the Web by extending HTML features.
January 2008
HTML 5 was published as a Working Draft by the W3C.
Although its syntax closely resembles that of SGML, HTML 5 has abandoned any attempt to be an SGML application and has explicitly defined its own "html" serialization, in addition to an alternative XML-based XHTML 5 serialization.. . |
Resources From :
http://en.wikipedia.org/wiki/HTML
