A Collateralized Loan Obligation (CLO) is a type of structured finance security backed by a pool of loans. CLOs are typically issued by banks and other financial institutions and are used to raise capital for lending activities. The loans in the pool are typically secured by collateral, such as real estate, equipment, or other assets. The CLO is then divided into tranches, or slices, with each tranche having a different level of risk and return. The tranches are then sold to investors, who receive payments from the underlying loans.