O reilly ado.net

ADO.NET is a new programming model built upon the .NET Framework, sharing a common type system, design patterns and naming conventions. The stated goals of ADO.NET are to:

Provide a disconnected (offline) data architecture in addition to supporting connected operation

Integrate tightly with XML

Interact with a variety of data sources through a common data representation

Optimize data source access
ADO.NET is designed to provide consistent access to data sources. This is accomplished through ADO.NET data providers that provide methods for connecting to data sources as well as retrieving, manipulating, and updating data in both connected and disconnected environments.