XML is a simple and flexible markup language in the text format. Nowadays, it is widely used to exchange a large variety of data over the Internet. XML consists of data as text in well-defined customized layouts by using self-defining tags. These user-defined tags are user friendly because they contain the name given by the user and make the information easily understandable to a user. These user-friendly features made XML to be widely used as a standard data-interchange format. The World Wide Web Consortium (W3C) frequently develops new standard for XML usage by different software vendors and solution providers. XML plays a very significant role with respect to .NET Framework 4.0. .NET Framework 4.0 provides us with a namespace called System.Xml, which includes classes that are used to work with XML.