Definition of "global attribute"

A global attribute is an attribute with a name allocated in the global attribute name partition associated with a specific namespace URI and therefore is independent of any specific element type. When an attribute is defined as a global attribute it is not limited to a single element type; various elements in the same namespace or even other namespaces can be defined to allow the attribute to be coded on those elements.

The HTML common attributes are one example of global attributes. However, unlike XML global attributes, which must always be explicitly prefixed, the HTML common attributes do not have a namespace prefix but are defined to be automatically associated with the HTML namespace. The consequence of this is that they will be processed as global attributes when the document is being processed as HTML or xHTML, but as local attributes when the document is being processed as pure XML.

Contrast with local attribute and the HTML common attributes, which are global attributes in HTML documents.