Special Edition Using XML, Second Edition

Types of XHTML

All the varieties of XHTML share a basic similarity: They adhere to the syntax and grammar of XML languages, and they are designed primarily for use on the Web to display and navigate through information and interactive applications. On the surface level, they are not very different from each other nor from earlier non-XML versions of HTML. The semantics and display characteristics of XHTML are inherited from HTML, so the meaning of any XHTML document should be familiar to authors of HTML.

XHTML 1.0 is the version of XHTML that is closest to HTML 4.01. In fact, XHTML 1.0 is defined primarily by reference to the HTML 4.01 specification. It's a direct translation from the looser SGML-based HTML into XML terms. No new language features ...