This document discusses interest rate derivatives, which are financial instruments derived from underlying interest rates or cash markets. Some popular types of interest rate derivatives are futures, forwards, options, and swaps. Interest rate derivatives allow investors to adjust portfolio positions more quickly and cheaply than transacting in the underlying instruments. They also provide more liquidity. Specifically, the document defines interest rate futures, swaps, caps, and floors, and discusses the markets for exchange-traded versus over-the-counter interest rate derivatives.