Whats a 10-second summary of DTDs?
DTDs (Data Type Definitions) check your document for “validity” (see other question). It contains the following pieces: • – Specifies the actual DTD (embedded), or where it can be found. • – Specify what elements are allowed in your XML file, and what those elements are allowed to contain. • – Specify the list of attributes which an element can contain • – Specify what should be substituted whenever an &entity; occurs DTDs are simple, easy to understand, but also limited in what they can, and can not, specify as valid. Probably you should be using schemas instead.
