A simple XHTML document, with the minimum of required tags:
The xmlns attribute is supported in all major browsers.
Note: The xmlns attribute is required in XHTML, but is invalid in HTML!
The xmlns attribute specifies the xml namespace for a document.
However, the HTML validator at http://w3.org does not complain when the xmlns attribute is missing in an XHTML document. This is because the namespace "xmlns=http://www.w3.org/1999/xhtml" is default, and will be added to the <html> tag even if you do not include it.
|http://www.w3.org/1999/xhtml||The namespace to use (for XHTML documents)|
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