The Document Object Model (DOM) is an interface
specification maintained by the W3C DOM Workgroup that
defines an application independent mechanism to access,
parse, or update XML data. In simple terms it is a
hierarchical model that allows developers to manipulate XML
documents easily Any developer that has worked extensively
with XML should be able to discuss the concept and use of
DOM objects freely. Additionally, it is not unreasonable to
expect advanced candidates to thoroughly understand its
internal workings and be able to explain how DOM differs
from an event-based interface like SAX.