Compound’s previous iterations employed a pooled-risk model, which supported nine cryptocurrencies, including ether (ETH), dai (DAI) and tether (USDT). Under the old model, users would deposit assets into lending pools, where their assets would earn interest. In exchange for their deposits, lenders received cTokens, which represented the value of their deposits. Using those cTokens, the lender could then borrow up to a certain percentage of the value of their collateralized assets in a different cryptocurrency.