The Document Object Model defines how an XML document is converted to an in-memory tree structure. The DOM is defined in a number of specifications at the W3C:

• The Core DOM defines the DOM itself, the tree structure, and the kinds of nodes and exceptions your code will find as it moves through the tree. The complete spec is at w3.org/TR/DOM-Level-2-Core/.
• Events defines the events that can happen to the tree, and how those events are processed. This specification is an attempt to reconcile the differences in the object models supported by Netscape and Internet Explorer since Version 4 of those browsers. This spec is at w3.org/TR/DOM-Level-2-Events/.
• Style defines how XSLT style sheets and CSS style sheets can be accessed by a program. This spec is at w3.org/TR/DOM-Level-2-Style/.
• Traversals and Ranges define interfaces that allow programs to traverse the tree or define a range of nodes in the tree. You can find the complete spec at w3.org/TR/DOM-Level-2-Traversal-Range/.
• Views defines an AbstractView interface for the document itself. See w3.org/TR/DOM-Level-2-Views/ for more information.