"XHTML 2 was a beautiful specification of philosophical purity that had absolutely no resemblance to the real world," said Bruce Lawson, HTML 5 evangelist for browser maker Opera. So what went wrong?

Do not deviate from the XHTML Basic document type. Using tags not supported by XHTML Basic almost guarantees rendering errors on a large percentage of mobile devices.

After the publication of HTML 4, and following a 1998 Workshop, W3C set forth to turn HTML into an XML-based format, called XHTML, due to the benefits of XML formats, the organization statement ...