Summary

Although DTDs certainly represent a technology that is sufficient for modeling XML document data, XML Schema provides a much more advanced alternative that is rapidly replacing DTDs for defining XML schemas. XSD schemas are constructed using the XSD markup language, which includes elements and attributes for describing the structure of custom XML-based markup languages. This means that you create XSD schema documents in the same manner as you create any other XML document, which makes XSD schemas immediately more accessible to XML developers than DTDs.

This hour explored the inner workings of XSD schemas and taught you the fundamental skills necessary to design and create them. After explaining the different types of XSD data and how to use each of them, the hour showed you a complete example schema created in XSD. Admittedly, XSD is a fairly complex topic that is a bit tough to absorb all at once. Much of the complexity can be eliminated if you rely on a schema tool such as those mentioned in this lesson.