The Document Object Model, commonly called the DOM, defines a set of interfaces to the parsed version of an XML document. The parser reads in the entire document and builds an in-memory tree, so your code can then use the DOM interfaces to manipulate the tree. You can move through the tree to see what the original document contained, you can delete sections of the tree, you can rearrange the tree, add new branches, and so on.

The DOM was created by the W3C, and is an Official Recommendation of the consortium.