XHTML

Extensible Hypertext Markup Language (XHTML), or simply XTML, is a markup language that has the same expressive possibilites as HTML, but conforms to the XML standard which is more strict. XHTML is a recommendation of the World Wide Web Consortium (W3C). Most of the recent versions of popular web browsers render XHTML properly, and many older browsers will also render XHTML as it is superficialy similar to HTML and most browsers do not require valid HTML. XHTML 1.0 was first recommended on January 26, 2000. Work is underway on XHTML 2.0.

XHTML's true power in unleashed when used in conjunction with Cascading Style Sheets. Although HTML can be used with CSS, XHTML moves to force its use for layout and style. This makes the separation of content and form an integral part of the webpage's code.

See also: HTML, XML, DTD