yearn.finance provides Decentralized Finance (DeFi) products which are vaults and earn. The purpose is to generate yields for users based on smart contracts such as Ethereum. Vaults are pools that automatically generate yields based on the opportunities in the market. With friendly user interface (UI), vaults simplify yield generation processes for end users. Therefore, users can generate passive income by investing in vaults without prior knowledge in the protocols or DeFi itself. Earn is a lending aggregator where funds are shifted between lending protocols in order to attain the highest yield. Users deposit stable coins into the Yearn pool, and then it will automatically be deposited into one of the three lending protocols (AAVE, dYdX, Compound). As interest rates between the protocols change, Yearn will automatically withdraw and deposit funds between the protocols to optimize interest rate. Both vaults and earn are simplified for end users.