
Document Type Definitions (DTD) • 103
XML document
Program A
Program B
Program C
Validate
Use this XML
document – No
need to validate!
(B) Situation in the presence of a DTD
DTD
Figure 3.3 Situation in the absence or presence of a DTD
As we can see, a DTD will free application programs from the worry of validating the contents of an
XML document. It will take this responsibility on itself. Therefore, the portion of validation is concentrated
in just once place – inside the DTD. All other parties interested in the contents of an XML document are free
to concentrate on what they want to do, i.e., to make use of the XML document the way they want and process ...