CDATA in XML is the character data is is not parsed by the XML Processor. If there is a section in the document that you do not want the XML processor to parse then it can be enclosed in <![CDATA[ ......................]]>
CDATA is used to store plain text or string values. It is commonly used with implied attributes which allows user to define their own values. For example <! ATTLIST Student LastName (CDATA) #IMPLIED>