Microsoft Business Connectivity Services (BCS) enables users to read and write data from external systems—through Web services, databases, and Microsoft .NET Framework assemblies—from within Microsoft SharePoint 2010 and Microsoft Office 2010 applications. Both SharePoint 2010 and Office 2010 applications have product features that can use external data directly, both online and offline. Developers can gain access to a rich set of features and rapidly build solutions by using familiar tools such as Microsoft Visual Studio 2010 and Microsoft SharePoint Designer 2010.

This diagram shows the relationship between all of the components that make up BCS or that interact with the services BCS provides.

SharePoint Business Connectivity Services Dataflow Model