Can more than one CLR version be present in a single machine?

i faced this question in开发者_Go百科 an interview, Is it possible to have more than one version of CLR in a single machine? pls provide me the details if u know - i mean if its not possible why? otherwise by default which one will be used?. Thanks!

Yes you can install 1.0, 1.1, 2.0 (up to 3.5) and 4.0 in the same machine...

But you can only host one version in each process (not sure if this changed with 4.0)..

Edit: A assembly is compiled against a specific CLR version and that CLR version will be used..

From MSDN

Starting with the .NET Framework version 4, you can use in-process side-by-side hosting to run multiple versions of the common language runtime (CLR) in a single process.

http://msdn.microsoft.com/en-us/library/ee518876.aspx