Converting HTML to XHTML 1.0
XHTML 1.0 is a reformulation of HTML 4.01 as an XML 1.0 application. Hence, XHTML 1.0 is almost identical to HTML 4.01. In order to make your HTML compatible with XHTML, some very simple rules need to be followed.
Review the following:
You may also need to refer to XHTML Document Type Definition (DTD) .