Why ADO.NET?

Likewise, if a database is Updated, the connection is opened long enough to complete the Update operation and is closed. By keeping connections open for only a minimum period of time, ADO .NET conserves system resources and provides maximum security for databases and also has less impact on system performance.
Also, ADO .NET when interacting with the database uses XML and converts all the data into XML format for database related operations making them more efficient.
napplication interacts with the database, the connection is opened to serve the request of the application and is closed as soon as the request is completed.