ADO.NET come from its previous version that is ADO. It is disconnected and ADO is connected on the other hand. Locking can also be done in ADO.NET and in it all the data can be map with the XML and One of most significance feature of ADO.NET is DataProvider.
This data provider can access diffreent data just like SQL, Oracle, Access and do some beautifull task like update, delete, insert and manage database. it provides object to achieve functionalities like opening and closing connection, retrieve data, update data and many more.There are the four main sections of a data provider.
(2) Command object
(3) Data Adapter
Datareader and Dataset are the two fundamental objects in ADO.NET. DataReader provides forward-only and read-only access to data on the other side. Dataset is a disconnected architecture while datareader is connected architecture.
There are some of data provider ADO.NET namespace:-
System.data :-Its contains objects that are used to access and store relational data example DataSet,DataTable, and DataRelation. Each of these is independent of the type of data source and the way we connect to it.
System.Data.OleDB:-Its contain objects that are for connecting to a data source with the help of OLE-DB provider, example OleDbConnection, OleDbCommand, etc. These objects comes from the common base classes and same properties, methods, and events as the SqlClient equivalents.
System.Data.SqlClient:-Its contains the objects that are used to connect to a data source TDS interface of Microsoft SQLServer.
System.XML:-Last but most important these day is System.XML its Contains the basic objects required to create, read, store, write, and manipulate XML documents according to W3C recommendations.
(1)OleDbConnection object is used with an OLE-DB provider
(2)SqlConnection object uses Tabular Data Services (TDS) with MS SQL Server
(3)System.Data.SqlClient is used for the sql database on the other hand System.Data.Oledb is used for data base that are in Access,Excel etc.