Basic .NET Framework : What is MSIL or CIL , What is JIT, What is a IL?

(IL)Intermediate Language is also known as MSIL (Microsoft Intermediate Language) or CIL (Common Intermediate Language). All .NET source code is compiled to IL. This IL is then
converted to machine code at the point where the software is installed, or at run-time by a Just-In- Time (JIT) compiler.