RFC 3236 (rfc3236) - Page 3 of 8

The 'application/xhtml+xml' Media Type

RFC 3236         The 'application/xhtml+xml' Media Type     January 2002


      Although conformant 'application/xhtml+xml' interpreters can
      expect that content received is well-formed XML (as defined in
      [XML]), it cannot be guaranteed that the content is valid XHTML
      (as defined in [XHTML1]).  This is in large part due to the
      reasons in the preceding paragraph.

   Published specification:
      XHTML 1.0 is now defined by W3C Recommendation; the latest
      published version is [XHTML1].  It provides for the description of
      some types of conformant content as "text/html", but also doesn't
      disallow the use with other content types (effectively allowing
      for the possibility of this new type).

   Applications which use this media type:
      Some content authors have already begun hand and tool authoring on
      the Web with XHTML 1.0.  However that content is currently
      described as "text/html", allowing existing Web browsers to
      process it without reconfiguration for a new media type.

      There is no experimental, vendor specific, or personal tree
      predecessor to 'application/xhtml+xml'.  This new type is being
      registered in order to allow for the expected deployment of XHTML
      on the World Wide Web, as a first class XML application where
      authors can expect that user agents are conformant XML 1.0 [XML]
      processors.

   Additional information:

      Magic number:
         There is no single initial byte sequence that is always present
         for XHTML files.  However, Section 5 below gives some
         guidelines for recognizing XHTML files. See also section 3.1 in
         [XMLMIME].

      File extension:
         There are three known file extensions that are currently in use
         for XHTML 1.0; ".xht", ".xhtml", and ".html".

         It is not recommended that the ".xml" extension (defined in
         [XMLMIME]) be used, as web servers may be configured to
         distribute such content as type "text/xml" or
         "application/xml".  [XMLMIME] discusses the unreliability of
         this approach in section 3.  Of course, should the author
         desire this behaviour, then the ".xml" extension can be used.







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