When a user deposits tokens to a Compound pool, they receive cTokens in return. These cTokens represent the individual’s stake in the pool and can be used to redeem the underlying cryptocurrency initially deposited into the pool at any time. For example, by depositing ETH into a pool, you will receive cETH in return. Over time, the exchange rate of these cTokens to the underlying asset increases, which means you can redeem them for more of the underlying asset than you initially put in — this is how the interest is distributed.