MimeTypes

There are two forms of the HTML language understood by most current browsers:

• text/html or classic HTML

HTML which is not well-formed XML and, though defined in HTML 4.0 and before using SGML DTDs, has always been parsed by browsers and other UAs using custom HTML parsers; no browsers use SGML parsers to parse HTML

• application/xhtml+xmlor XHTML

HTML which is well-formed XML and defined in XHTML 1.1 and before by an XML DTD and is intended to be parsed by UAs using XML parsers (note that most current browsers also recognize XHTML when served with the application/xml and text/xml MIME types, but no version of Internet Explorer correctly recognizes XHTML)