Special Edition Using XML, Second Edition

DTDs

Because DTDs aren't actually a separate recommendation, but a part of the XML 1.0 Recommendation, there aren't very many DTD specific resources available. However, there are a few places where you can turn to learn more about Document Type Definitions.

• XML's DTD (http://www.w3.org/XML/1998/06/xmlspec.dtd)— This is the DTD that describes XML itself. Although you probably won't have a need to consult this DTD, it can be interesting to see how the DTD is structured.

• Converting an SGML DTD to XML (http://www.xml.com/pub/a/98/07/dtd/index.html)— This article can be helpful if you have an SGML DTD that you need to convert to XML. Because SGML is a much older technology, a number of DTDs are available for different uses in SGML.

• XML 101 DTDs (http://www.xml101.com/dtd/default.asp ...