This page summarizes the relationships among specifications, whether they are finished standards or drafts. Below, each title links to the most recent version of a document. For related introductory information, see: Components.
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Group Notes are not standards and do not have the same level of W3C endorsement.
This document defines the meaning of the attribute
These specifications have either been superseded by others, or have been abandoned. They remain available for archival purposes, but are not intended to be used.
Since XML 1.0, the ability of processors to identify an XML element by an explicit identifier ("IDness") has depended upon validation. Both DTDs and [XML Schema] have mechanisms to identify the structures containing unique identifiers. But neither XML Schema nor DTDs are required by all processors. A common processor type does not perform validation, nor fetch external resources for the purpose of acertaining whether the document contains unique identifiers.
This document sets out the requirements for a mechanism for determining "IDness" applicable to all classes of XML processors.