The Annotated XML Specification
Inside the XML 1.0 Specification
If you want to understand XML, you have to read the specification. However, to really get inside the specification and understand why it says what it does, you need an expert guide. Tim Bray, co-editor of the XML 1.0 specification, shares his knowledge and insights about XML, SGML and the working group behind the specification in this annotated version of the document.
Tim created the Annotated XML Specification in XML, and wrote an excellent explanation of how he did this.
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