Winows Forms is the name given to the graphical user interface application programming interface (API) included as a part of Microsoft's .NET Framework, providing access to the native Microsoft Windows interface elements by wrapping the existing Windows API in managed code. While it is seen as a replacement for the earlier and more complex C++ based Microsoft Foundation Class Library, it does not offer a paradigm comparable to model-view-controller. Some after-market and third party libraries have been created to address this issue. The most widely used of these is the User Interface Process Application Block, which is released by the Microsoft patterns & practices group as a free download that includes the source code to the core library and quick start examples.