W3C Releases XML Schema Recommendation

It took two and a half years, but the World Wide Web Consortium (W3C) has finally released its XML Schema Recommendation. The W3C XML schema defines shared markup vocabularies and the structure of XML documents that use those vocabularies, and it provides hooks to associate semantics with them.

"There are those who would say that this is the most important technical news to come out of the W3C this year," said Janet Daly, the group's head of communications. "Certainly for those in the XML developer community, who have been waiting for this for quite a while, it's probably the technical announcement of the year."

"With [XML] Schema, you are able to do a variety of things, from a business-to-business perspective, that are absolutely critical for successful and thorough implementations that may exist on the Web," said Daly. "Schema allows you to bring a measure of the functionality that databases have to the Web in a language that was made for it."

According to Daly, a W3C recommendation indicates that a specification is stable, contributes to Web interoperability, and has been reviewed by the W3C membership, whose members are in favor of supporting its adoption by academic, industry, and research communities.

This recommendation resulted from the efforts of the XML Schema Working Group, whose roster includes dozens of IT leaders, including Commerce One, Hewlett Packard, IBM, Informix, Intel, Lotus, Microsoft, Oracle, SAP, Sun Microsystems, and Xerox, among many others.

"XML Schema makes good on the promises of extensibility and power at the heart of XML," said W3C Director Tim Berners–Lee in a media release. "In conjunction with XML Namespaces, XML Schema is the language for building XML applications."

Along with the schema spec announcement, the W3C unveiled its new XML Schema Validator, which it co-developed with the University of Edinburgh. The validator has been revised at each stage of XML Schema development, Daly said, and now provides validation against the XML Schema Recommendation.

The W3C ( is an international industry consortium whose mission is to develop common protocols that promote the evolution of the Web and ensure its interoperability. The group is run jointly by the MIT Laboratory for Computer Science in the USA, the National Institute for Research in Computer Science and Control in France and Keio University in Japan.

About the Author

John K. Waters is a freelance writer based in Silicon Valley. He can be reached at [email protected].