CDATA Sections:

CDATA sections are used to display markup without the XML processor trying to interpret that markup. They are particularly useful when you want to display sections of XML code.

<![CDATA[

any characters (including markup)

]]>

Example:
<?xml version="1.0"?>
<!DOCTYPE body [
	<!ELEMENT body (#PCDATA)>
]>

<body>

	<![CDATA[
	
	Here is an example of an internal DTD:
	<!DOCTYPE lab_group [
		<!ELEMENT lab_group (student_name)*>
		<!ELEMENT student_name (#PCDATA)>
		<!ATTLIST student_name student_no ID #REQUIRED>
		<!ATTLIST student_name tutor_1 IDREF #IMPLIED>
		<!ATTLIST student_name tutor_2 IDREF #IMPLIED>
	]>

	]]>

</body>

Rules: