a)Data can not be stored in the form of rows and columns as in Databases. Semi-structured data contains tags and elements (Metadata) which is used to group data and describe how the data is stored. Similar entities are grouped together and organized in a hierarchy.
b)Retrieving information from XML files by using the Document Object Model, XmlReader class, XmlDocument class, and XmlNode class. Synchronizing DataSet data with XML via the XmlDataDocument class. Executing XML queries with XPath and the XPathNavigator class