The XHTML Role Attribute Module is a W3C Working Draft, which provides a single attribute to be used in documents to indicate the purpose an element.
The document is the work of the W3C's XHTML Working Group, and the editors are:
Mark Birbeck, webBackplane
Shane McCarron, Applied Testing and Technology, Inc.
Steven Pemberton, CWI
T. V. Raman, Google, Inc.
Richard Schwerdtfeger, IBM
From the abstract:
The XHTML Role Attribute defined in this specification allows the author to annotate XML Languages with machine-extractable semantic information about the purpose of an element. Use cases include accessibility, device adaptation, server-side processing, and complex data description. This attribute can be integrated into any markup language based upon XHTML Modularization.