A standard interface for representing XML and HTML documents. The data is parsed into a tree of objects, which a programmer can navigate and manipulate. It is especially relevant to web browsers, and in particular to the implementation of dynamic HTML. The World Wide Web Consortium released the first version of the DOM (level 1) in 1998, although a previous intermediate version (level 0) had already been incorporated in HTML 4; levels 2 and 3 have subsequently been released. Adoption of the DOM by web browsers—which had previously implemented idiosyncratic and incompatible models—was initially slow and is still not uniform.

http://www.w3.org/DOM/ The WSC’s DOM page