Here is a free Mac OS X utility by Todd Ditchendorf for all you concerned web designers out there. XML Nanny allows you to validate your XML and XHTML documents (either locally or over a network ...

XHTML 2, a technology intended to build a more powerful Web from the ground up, ... The X in XHTML stands for XML, which in turn stands for Extensible Markup Language.

From where I'm standing it doesn't seem to be possible to mix XHTML and PHP.<BR><BR>Thus far I've just been using mixing basic HTML and PHP together and everyone is happy.

You would use XML if you 'consume' any web services (see W in this series - Do you speak my language: W is for Web services, Wiki, W3C, Webserver, WWW, Wordpress), or you could use XML if you use ...