.NET is a set of application interfaces implemented as a .NET class library. This class library is used by VB .NET (and the other managed code languages, C# and managed C++) to provide programmatic access to databases. There are three basic kinds of classes.
Command and DataAdapter
Connection classes provide the properties and methods needed to open a channel to a database. This may be a network connection, in the case of SQL Server or other server-based database systems, or a file handle, in the case of desktop databases such as Microsoft Access (JET) databases or Excel files.
Command and DataAdapter classes provide the means to execute queries and return data from the database objects referenced ...