Relax Ng

RELAX NG (REgular LAnguage description for XML Next Generation).

The "next generation" part was the work of OasisOrganization.

RelaxNg has been adopted by ISO as a standard for DSDL (Document Schema Definition Language). See earlier draft at From the charter at :

The purpose of this committee is to create a specification for a schema language for the ExtensibleMarkupLanguage based on TREX and RELAX. The key features of RELAX NG are that it is simple, easy to learn, uses XML syntax, does not change the information set of an XML document, supports XML namespaces, treats attributes uniformly with elements so far as possible, has unrestricted support for unordered content, has unrestricted support for mixed content, has a solid theoretical basis, and can partner with a separate datatyping language (such W3C XmlSchema Datatypes).

-- AndrewJoyner

Links for RelaxNg ancestors:
RelaxNg is reported in XmlEurope2004 to have superseded XmlSchema in market adoption due to its simplicity over the latter. (see


Relax NG tutorial from Oasis

Technology report from Oasis

Compact Syntax tutorial

A simpler schema Language for XML

RelaxNg online book

Comparison with XmlSchema

More comparisons, with code examples

Free Xml tools

Schema tutorial XmlSchema and RelaxNg

RelaxNg QuickQuestions

Q What is the extent of support of RelaxNg by tools as at end 2004? Are there free and commonly used tools available for the MicrosoftWindows environment before DotNet came out?

A see for editors (e.g. XML Operator) and converters (e.g. trang & DTDinst)

Q What is RELAX, and what is the NG in the RelaxNg stand for? And why should someone who need to do a bit of Xml care about RelaxNg?

A RELAX NG (pronounced "relaxing") is a grammar-based schema language. The NG stands for New Generation. See ISBN 0596004214

See also SchemaLanguagesForXml


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