The ActiveX Data Objects (ADO) .NET is the main data provider for database access for any CLR-based application. ADO.NET was designed to supercede the old ADO. ADO used to be another framework for database access and manipulation. It works as a middleware, similar to a control or component, able to make available underlying database features as simplified features. It uses ActiveX technology (which is the heir to COM and OLE) to encapsulate its features as reusable cross-language features. This is why ADO was able to work in applications made with Visual Basic 6 or C++. ADO.NET, instead, is available only to CLR-based applications. As the ADO could, ADO.NET can also interact with any database using a specific data provider or cross provider, such as OLEDB or ODBC.

ADO.NET is completely extensible with a full interface-based architecture, relying on the abstract factory pattern. This makes the framework usable in situations other than in a classical tightly-coupled scenario with...