Pendle is a protocol that enables the trading of future yield for a yield-generating token through its AMM system. It achieves this by splitting an underlying yield generating token in to its Ownership Token (OT) and future Yield Token (YT). YT represents the yield of the underlying asset and can either be sold to earn the future income immediately, or purchased to be exposed to pure yield of the underlying. Both YT and OT can be further used to provide liquidity into Pendle to earn extra yield.