Web Design in a Nutshell, 3rd Edition

Identifying media type and character encoding

It is recommended (although not required) that the media type and character encoding be specified within (X)HTML documents as a way to keep that information with the document. (For more information on declaring character encodings, see Chapter 6.)

This is done using the meta element, as shown in this example:

    <metahttp-equiv="content-type" content="text/html; charset=UTF-8" />

The parts are broken down as follows:

Media type identification

The media type, very similar to MIME types used for sending email attachments, is another bit of information sent in the HTTP header. For HTML documents, the media type is always text/html. That one is easy. XHTML documents, on the other hand, are not as straightforward.

XHTML 1.0 documents may be served as either XML or HTML documents. Although XML is the proper method, due to lack of browser support for XML files, many authors choose to deliver XHTML 1.0 files with the text/html MIME type used for HTML documents. When XHTML documents are served in this manner, they may not be parsed as XML documents.

XHTML 1.0 files may also be served as XML using the MIME types application/xhtml+xml, application/xml, or text/xml. The W3C recommends that you use application/xhtml+xml only.

XHTML 1.1 documents are not permitted to use the text/html media type. This poses a problem because some browsers do not know what to do with the non-text/html media types. This is another reason why XHTML 1.1 is still difficult to ...