Multi Targeting in .NET
From VS 2008 they have added multi-targeting feature. You can use same visual studio with different versions of .NET framework. So in previous versions of Visual studio, every version was tied-up with its framework. For example VS 2003 only works with 1.1 framework whereas VS 2005 works with 2.0.
Project created in VS 2008 or after that onwards edition if you click on project properties you can now change the framework version to different types and check if your code is compatible with old version.
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