Microsoft Office SharePoint Server 2007, commonly abbreviated to MOSS, is the successor to Microsoft Office SharePoint Portal Server 2003. It has a large range of new features not in the previous version. The application uses a Microsoft SQL Server back-end for storing data. The front-end consists of ASP.NET pages served via Internet Information Services (IIS) on Windows Server 2003. MOSS 2007 requires .NET Framework 3.0 (with Windows Workflow Foundation) to be installed.