BCS

Microsoft Business Connectivity Services (BCS) (formerly named the Business Data Catalog) provides read/write access to external data from line-of-business (LOB) systems, Web services, databases, and other external systems 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 using familiar tools such as Microsoft Visual Studio 2010 and Microsoft SharePoint Designer 2010.

Business Connectivity Services enhances Office application and SharePoint application capabilities and their user interface (UI) through features, services, and tools. These enhanced capabilities and UI streamline development of solutions with deep integration of external data and services. Experienced users, developers, and business unit IT professionals can integrate assets from external systems and enable interaction with the external data through many types of Office client and server applications. The Business Connectivity Services feature set enables rapid development and deployment of scalable and security-rich solutions. The following diagram shows a high-level view of Business Connectivity Services.