UNKNOWN_NODE (0)             The node type is unknown (not part of DOM)

 ELEMENT_NODE (1)                The node is an Element.
 ATTRIBUTE_NODE (2)              The node is an Attr.
 TEXT_NODE (3)                   The node is a Text node.
 CDATA_SECTION_NODE (4)          The node is a CDATASection.
 ENTITY_REFERENCE_NODE (5)       The node is an EntityReference.
 ENTITY_NODE (6)                 The node is an Entity.
 PROCESSING_INSTRUCTION_NODE (7) The node is a ProcessingInstruction.
 COMMENT_NODE (8)                The node is a Comment.
 DOCUMENT_NODE (9)               The node is a Document.
 DOCUMENT_TYPE_NODE (10)         The node is a DocumentType.
 DOCUMENT_FRAGMENT_NODE (11)     The node is a DocumentFragment.
 NOTATION_NODE (12)              The node is a Notation.

 ELEMENT_DECL_NODE (13)          The node is an ElementDecl (not part of DOM)
 ATT_DEF_NODE (14)               The node is an AttDef (not part of DOM)
 XML_DECL_NODE (15)              The node is an XMLDecl (not part of DOM)
 ATTLIST_DECL_NODE (16)          The node is an AttlistDecl (not part of DOM)

 Usage:

   if ($node->getNodeType == ELEMENT_NODE)
   {
       print "It's an Element";
   }



##</code><code>##

 @list = $node->getElementsByTagName("tag");       # returns a perl list
 $nodelist = $node->getElementsByTagName("tag");   # returns a NodeList (object ref.)
 for my $elem ($node->getElementsByTagName("tag")) # iterate over the result nodes