Gustavo,

>I know that this question maybe dumb, but what's CLR?

The Common Language Runtime (CLR) is part of the new .NET framework that Microsoft announced earlier this year. The CLR will run "managed code" created by VB7, C#, and optionally by C++. This allows the languages to inherit classes from each other and many other features.

Read up on it all at:

http://www.microsoft.com/net/
http://msdn.microsoft.com/vstudio/nextgen/default.asp
http://msdn.microsoft.com/net/default.asp