At the conference, the World Wide Web Consortium released XML Schema as a W3C Recommendation, finalising efforts that started in 1998 to define a standard way of describing Extensible Markup Language document structures and adding data types to XML data fields.
Now that it is finally out, the long-delayed XML Schema standard will catalyse the next big step in XMLâ€"-allowing cross-organisational XML document exchange and verification.
Just as discovery of the Rosetta stone in 1799 provided a way to fix the meaning of Egyptian hieroglyphs so they could be understood across the gulf of two millennia, XML Schema provides a way for organisations to fix the meaning of XML documents so they can be understood across the gulf of organisational boundaries and otherwise incompatible IT architectures.
As a result, XML Schema will be a cornerstone in the new e-commerce architecture that we are collectively building and will be a vital component for making business exchanges and other loose associations of trading partners possible.
The arrival of XML Schema, more than three years after XML itself, has left many chafing at the bit (and others, such as Microsoft, running off in their own direction implementing and shipping products based on prestandard efforts), and the market is now more than ready for this standard to take hold.
However, XML Schema's long development cycle gave vendors time to understand the specification and start writing compliant software, and we are now seeing the rapid release of XML Schema-compliant (or soon-to-be-compliant) authoring tools and servers.
A little of everything
That long, committee-driven development cycle also resulted in a specification that has a bit of everything in it, and fully compliant XML Schema parsers will have to be complex pieces of software to support all the options the specification allows.
Fortunately, XML Schema documents have to reference only the functionality they need, and the more complex options in XML Schema, such as null elements and explicit types, may just fade away through disuse.
The W3C recently published a recommendation on how to group Extensible HTML, the consortium's replacement for HTML, into well-defined subgroups so XHTML browsers (such as those in cellular phones) can clearly define which parts of the language they support and which they don't.
Something similar is a possibility for XML Schema if the full specification proves too difficult to implement for some vendors (although large players such as IBM, Microsoft and Oracle are moving ahead full speed with plans to support the full specification as published).
Over the next few years, eWEEK Labs predicts XML Schema will become integral to the way that many companies exchange information.
XML Schema is clearly needed in today's e-business arena; it makes sense and is the logical next step forward for XML, the single most important enabling technology of business-to-business communication.
