XML Schema
W3C XML Schema, published as a Recommendation in May 2001 (XMLS0, XMLS1, XMLS2) acknowledges the influence of DCD, DDML, SOX, XML-Data, and XDR in its list of references and appears to have picked pieces from each of these proposals but is also a compromise between them. The main sponsors of the two languages still actively used and developed (Microsoft for XDR and Commerce One for SOX) have both announced that they would support W3C XML Schema for their new developments, and W3C XML Schema should become the only surviving member of this family.
See also
XML, DTD (Document Type Definition), PSVI, RELAX NG, DSDL
