Microsoft Business Connectivity Services (BCS), formerly named the Business Data Catalog, enables users to read and write data from external systems—through Web and Windows Communication Foundation (WCF) 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.