The Compound is an Ethereum based protocol facilitating borrowing and lending of ERC20 tokens. Interest in Compound is calculated in real-time, the interest is calculated per block and each lender receives the same interest. Interest is paid per block, lenders can lend for any period and they will earn interest accordingly. Tokens can be withdrawn instantaneously. Interest is paid in the same asset as it is being lent. Interest is paid into the supply balance, which is then re-lent automatically.

There is a 0.025% origination fee for the borrower and the lenders have to pay

10 to 15% of the passive income interest earned, back to the compound developers. ETH needs to be wrapped to be lent out resulting in WETH.