XHTML
Introduction
e
Xtensible
Hyper
Text
Markup
Language is a reformulation of
HTML 4.01 as an
XML 1.0 application. XHTML provides more robust, richer and extensible features than HTML. The latest version of XHTML is 1.1.
Beside favoring a better
DOM tree for better rendering, XHTML allows some features to be extended. However, There is a school of thought that says the XHTML 1.0 flavours are better than their HTML 4.01 counterparts. This isn't really true; there is nothing that can be expressed in XHTML 1.0 that cannot be expressed in the corresponding flavour of HTML 4.01. In particular, XHTML 1.0 Strict is no more or less a reliable data source than HTML 2.0
assuming both are valid.
See also
WebStandard for XHTML validators.
Links
XHTML 1.1 and 2.0
<object>
Others