SDF -- A file format that is compliant with the combination of SQL Server 2005 Compact Edition, SQL Server 2005 and Visual Studio 2005 to build, test, deploy, and manage applications for users. Databases of this type can be accessed directly as a datasource, e.g., from Visual Studio 2005, or from SQL Server Management Studio. As such, they can be passed around with programs or projects, although they are mainly used for embedded applications. The file includes all necessary code points to access the data, and so does not require an instance of SQL Server to be installed.