Document Definition Markup Language (DDML) Specification, Version 1.0
Ronald Bourret, J Ron Cowan, Ingo Macherius, Simon St. Laurent · TUbilio (Technical University of Darmstadt) · 1999
This document proposes Document Definition Markup Language (DDML), a schema language for XML documents. DDML encodes the logical (as opposed to physical) content of DTDs in an XML document. This allows schema information to be explored and used with widely available XML tools. DDML is deliberately simple, providing an initial base for implementations. While introducing as few complicating factors as possible, DDML has been designed with future extensions, such as data typing and schema reuse, in mind.