Unity is amazing. With minimal effort you can have a prototype up and running in a few hours. No other engine has allowed such great flexibility. Another of Unity's excellent features is the ability to program in three languages, namely C#, UnityScript, and Boo. Let's go in to the pros and cons of each one, and explain which one we'll be using.
Boo is an object-oriented, statically-typed programming language that has a syntax inspired by Python. Boo has only been covered here for completeness, the documentation for programming in Unity with Boo is poor to non-existent and only around 5 percent of Unity developers actually use Boo, so finding support when you need it could prove difficult.