The Managed Extensibility framework or MEF is a framework released as part of .NET 4 and Silverlight that provides a mechanism to dynamically compose an application at runtime out of loosely coupled parts and provides a variety of mechanisms to discovering these parts. You can think of this as an implementation of a plugin framework that enables plugging in functionality into a container, based on information available at runtime. The most notable example of a MEF client is the Visual Studio 2010 ......