DOMDocument’s Node Types
from: http://www.webreference.com/js/tips/020131.html
The DOMDocument object is based on a tree structure. There are twelve different node types on this tree, from 1 to 12. Here they are, with their corresponding nodeTypeString property values:
Type
nodeTypeString
1
"element"
2
"attribute"
3
"text"
4
"cdatasection"
5
"entityreference"
6
"entity"
7
"processinginstruction"
8
"comment"
9
"document"
10
"documenttype"
11
"documentfragment"
12
"notation"