The data object model is a set of custom .NET Framework classes that relate to data in a database or a file. You can use LINQ to SQL or the Entity Framework to map classes directly to an underlying database, but often the ideal design for a relational database and an object-oriented set of classes aren’t exactly the same. When the two designs don’t match, you can alter the design of your classes while still connecting directly to the underlying database.

At times, database developers might change the database schema. You don’t necessarily have to change your data object model, however. In fact, you have the option of abstracting the database schema from your application and modifying the data object model mappings without recompiling your application. This can simplify application upkeep in enterprise environments.