"Parts is Parts" >Page 1, 2
Part 1 is the Functional Specification. Translated this means it's the part of the spec that describes what exactly the standard is supposed to do. Part 2 the Scene Authoring Interface describes the methods for exactly how programs interface to the data structures using several languages and the W3C interface specification the DOM. Parts 3, 4 and 5 are three different encodings of the data structures (the 3D scene graph). Part 3 is the UTF-8 encoding otherwise known as good 'ole fashioned VRML97 encoding. Part 4 is the XML encoding, and Part 5, which is not being worked on, is a binary encoding which will someday allow for much more compact file sizes.
Most of the effort to date has been spent on Part 4 the XML encoding. More specifically the XML DTD. A DTD is to XML the way a blueprint is to a house. There was and to some extent still is a fair bit of discussion, arguments, spirited technical questions about the particular DTD. The end goal of all however, is to create the right house.
One of the over arching and most laudable goals of the XML encoding of a 3D file format, is to integrate 3D with the Web. XML is becoming the dominant file format for the Web. The cool thing about XML is that it's a meta-language. You can define other markup languages using XML. HTML, can in fact, be completely described as an XML DTD. As another example of the trend towards XML the W3D (world wide web consortium) is turning HTML into an extensible language via XHTML. The hope is to turn VRML200x into a first class file format fully integrated with the Web. Time will tell!
It's also important to understand that you can get involved in the ongoing development process. It's open to all. If you're so inclined I'd also recommend joining the Web3D Consortium. For as little as $100 you can become a professional member.
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