Provides an older in-memory Extensible Markup Language (XML) programming interface that enables you to modify XML documents. Developers should prefer the classes in the System.Xml.XDocument package. Commonly Used Types: System.Xml.XmlNode System.Xml.XmlElement System.Xml.XmlAttribute System.Xml.XmlDocument System.Xml.XmlDeclaration System.Xml.XmlText System.Xml.XmlComment System.Xml.XmlNodeList System.Xml.XmlWhitespace System.Xml.XmlCDataSection When using NuGet 3.x this package requires at least version 3.4.