Document Type Definitions

• Definition of product node

  <! ELEMENT product (description, price)>

• The other nodes

  <!ELEMENT quantity (#PCDATA)>
  <!ELEMENT description (#PCDATA)>
  <!ELEMENT price (#PCDATA)>
  

• #PCDATA refers to text, called "parsed character data" in XML terminology
  • Can contain any characters
  • Special characters have to be replaced when they occur in character data