- is called
- XML Schema
- is based on
- XML
- uses namespace
- http://www.w3.org/2001/XMLSchema (usual prefix: xsd)
With XML Schema you can describe (in XML) how certain XML documents have to look like. It is similar to doctype definitions, but it is much mightier. With XML Schema you can not only describe the structure of a document, you can also define XML datatypes.
Start with reading the primer.
Specifications
XML Schema Part 0: Primer Second Edition
http://www.w3.org/TR/xmlschema-0/
type: W3C Recommendation
date: 2004-10-28
XML Schema Part 1: Structures Second Edition
http://www.w3.org/TR/xmlschema-1/
type: W3C Recommendation
date: 2004-10-28
XML Schema Part 2: Datatypes Second Edition
http://www.w3.org/TR/xmlschema-2/
type: W3C Recommendation
date: 2004-10-28