Explain it to me like I am a 5 year old: Derivatives (Futures, Forwards, Swaps, Options)

I am a graduate student pursuing Masters in Computer Science from NYU wanting to understand finance and many of the underlying concepts. This post is meant for people who are completely new to Finance but want to have a basic understanding of the stock market. My aim here is to make the concepts easier and more understandable.

What do you mean by Derivative?