HTML
Hypertext Markup Language (HTML) is a markup language designed for creating web pages, that is, information presented on the World Wide Web. Defined as a simple "application" of SGML, which is used by organizations with complex publishing requirements, HTML is now an Internet standard maintained by the World Wide Web Consortium (W3C). The specification for the last version, 4.01, is available there.
HTML generally appears in text files stored on computers connected to the World Wide Web. These files contain information in plain text mixed with markup, that is, instructions for the program on how to display ( the web browser is used to display) or process the text (generally, the HTML editor is used for this). There are three kinds of markup elements in HTML:
- structural markup that describes the purpose of text (for example,
<h1>Golf</h1>will cause a reader to treat "Golf" as a first-level heading), - presentational markup that describes the physical appearance of text regardless of its function (for example,
<b>boldface</b>will render boldface text), and - hypertext markup that links parts of the document to other documents (for example,
<a href="http://www.wikipedia.org/">Wikipedia</a>will render the word Wikipedia as a hyperlink to the specified URI).
As with many Internet standards, the popularity and technological advancement of the World Wide Web grew much faster than standards bodies could track, so there are some incompatible proprietary versions of HTML still in use, though standards are improving. But nowadays most features of HTML4 are implemented by the major browsers. HTML4 gives a fairly comprehensive set of formatting options, however most of these have been deprecated in favor of stylesheet languages like CSS, which should be used for formatting, while HTML should be used for describing the structure and the logic of the page only.
Version history of the standard:
- HTML 2.0 (RFC 1866) approved as a proposed standard -- 22nd September 1995,
- HTML 3.2 -- 1996,
- HTML 4.0 -- 18th December 1997,
- HTML 4.01 (minor fixes) -- 24th December 1999,
- ISO/IEC 15445:2000 ("ISO HTML") -- 15th May 2000.
There is no HTML 1.0 specification because there were multiple informal HTML standards at the time and so the formal specification was given the version number 2.0 in order to distinguish it from these.
There will no longer be any new versions of HTML. However, HTML lives on in XHTML, which is based on XML.