What is JIT compilation?

Purpose:

• This question prods whether the developer has a proper grasp of the .NET framework and is familiar with terms that surround it's implementation.
• Familiarity with .Net constructs are a good sign that a developer knows what he/she is doing, a but its a better warning sign if a developer falters on these types of questions.

Potential Answer:
JIT refers to Just in Time Compiler and is part of the Common Language Runtime (CLR). It manages the execution of all .NET programs and takes Intermediary Language and compiles it for running as native code/instructions.