The Microsoft ADO.NET Entity Framework has become the standard for database access in .NET applications. DevForce builds upon the Entity Framework and most DevForce applications model and access data with the Entity Framework.
Get started learning about the Entity Framework on MSDN.
The April 2012 Microsoft white paper, Performance Considerations for Entity Framework 5 is essential reading for every Entity Framework developer using any version of EF (not just version 5). It carefully explains how EF evaluates your model, which steps are expensive, and things you can do to improve the performance of your EF activities.