Schemas are tools for describing document structures and content.
XML Authority uses the term 'schema' to describe both DTDs and the various other schema proposals, including DCD, DDML, SOX, XML-Data, and the schema standards currently under development at the W3C. XML Authority provides a consistent interface you can use when working with any of these schema formats. More information on each of the newer schema formats is available at the W3C . The list below includes links to the documentation for the format. XML Schema - Structures and Datatypes . This is the emerging W3C specification, still under development but on the way toward becoming a W3C Recommendation.