XHTML Modularization: the Second Step

A decomposition of XHTML 1.0 into a collection of abstract modules that provide specific types of functionality - allow subsets, extenstions, combination with other XML vocabularies

Also defines a way to develop your own modules that can be combined with XHTML modules

Modularization of XHTML became a Recommendation on 10 April 2001 including DTD implementation, Modularization of XHTML in XML Schema is in progress (Last Call soon)