.NET Multi-Targeting Packs for Visual Studio 2010

What Are Targeting Packs?
Microsoft provides a set of “Multi-Targeting Packs”, to provide Microsoft Visual Studio and other developer tools with a structured system for targeting .NET platforms. The primary content of these targeting packs is reference assemblies, which describe the APIs supported by a given .NET platform version. Compilers and other tools and services can consume these assemblies to provide a high-fidelity representation of that .NET platform version.

Learn more about the above : http://msdn.microsoft.com/en-us/hh454951.aspx

Complete information about the VS 2010 pack, use the below link to see

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