The Microsoft.XmlDiffPatch namespace contains classes which allow you to compare two XML documents. You can use the XmlDiff class to produce a third XML document, called an XML Difference Language (XDL) Diffgram, which lists the differences between the source documents, and you can use the XmlPatch class to recreate the changed document. You can specify details of how the differences are computed using the XmlDiffOptions and XmlDiffAlgorithm enumerations.