Have you worked with ADO.net? Can you explain to me in brief ?

Yes I have certainly worked on ADO.Net. ADO.net encompasses two groups of classes: content components and managed provider components. The content components include DataSet class and other supporting classes as DataTable, DataRow, DataColumn and DataRelation. The DataSet class is a lightweight cache of a particular database from the data store.  It allows reading and writing of data and schema in XML. ADO.Net involves disconnected datasets because it is geared towards a distributed architecture. All tables and relations in a DataSet are exposed through the DataSet tables and Relations properties. 
E.g.
Using System;
Using System.Data; 
DataSet ds = new DataSet(“MyDS”);
Ds.Tables.Add (“Order”);
Ds.Tables[“Order”].Columns.Add(“OrderNo” Type.GetType(“System.Int32”)); 
The DataSet tightly integrates with XML using the methods WriteXml, ReadXml, WriteXmlSchema and ReadXmlSchema