The documentation for XML for <SCRIPT> is broken up into five sections:

Overview: Documentation layout and philosophy
FAQ: Information on licensing and other general items
W3C DOM Parser: Documents the W3C DOM Parser & gives code examples
Classic DOM Parser: Documents the DOM Parser & gives code examples
SAX Parser: Documents the SAX Parser & gives code examples
Server-Side Proxies: Documents the server-side Proxies & gives code examples
Tools: Documents the extra tools included with XML for <SCRIPT>

For a more in-depth understanding of XML for <SCRIPT>, you are highly encouraged to look at the source code for the test suites and the example applications. These demonstrate "real life" usage of the parsers and give a very good overview of the capabilities of the code.