The Microsoft .NET Compact Framework (.NET CF) is a version of the .NET Framework that is designed to run on resource constrained mobile/embedded devices such as personal digital assistants (PDAs), mobile phones, factory controllers, set-top boxes, etc. The .NET Compact Framework uses some of the same class libraries as the full .NET Framework and also a few libraries designed specifically for mobile devices such as .NET Compact Framework controls. However, the libraries are not exact copies of the .NET Framework; they are scaled down to use less space.