System.Xml namespace in .NET Framework Class Library
The System.Xml namespace provides standards-based support for processing XML. The supported standards are: XML 1.0, XML Namespaces, XSD Schemas, XPath expressions, XSLT transformations, DOM Level 1 Core, and DOM Level 2 Core.
In addition to W3C DOM-compliant interfaces, System.Xml provides optimized pull-based readers and optimized writers. Finally, System.Xml provides an easy-to-use XML binding library (XML Serialization).