What is XHTML?
The Extensible Hypertext Markup Language, or XHTML, is a hybrid between HTML and XML that is more universally acceptable in Web pages and search engines than XML. Both standards are powerful, but XHTML is significantly better than HTML.
XHTML uses three XML namespaces (used to qualify element and attributes names by associating them with namespaces identified by URI references. Namespaces prevent identically custom-named tags that may be used in different XML documents from being read the same way), which correspond to three HTML 4.0 DTDs: Strict, Transitional, and Frameset.
A character encoding may be specified at the beginning of an XHTML document in the XML declaration when the document is served using the application/xhtml+xml MIME type. (If an XML document lacks encoding specification, an XML parser assumes that the encoding is UTF-8 or UTF-16, unless the encoding has already been determined by a higher protocol.)
< ?xml version="1.0" encoding="UTF-8"?>