XML Schema is a XML-based description of a type of XML document, typically expressed in terms of constraints on the structure and content of documents of that type, beyond the basic syntactical constraints imposed by XML itself. Questions should use xmlschema tag for questions related to XML Schema or schema-related tools. Use xsd tag for the XML Schema Definition language.
XML Schema describes the structure of an XML document with the XML Schema language, which is also referred to as XML Schema Definition (XSD).
XML Schema builds on the basic concepts in XML 1.0 and Namespaces. XML defines content with elements and attributes, and XML Schema defines which elements and attributes as well as in which order they may appear and other constraints in a particular class of XML instances.
In XML Schema, there is a basic difference between complex types which allow elements in their content and may carry attributes, and simple types which cannot have element content and cannot carry attributes (e.g., integers, strings, etc.).
See Also: