Collateralized Mortgage Obligations (CMOs) are financial instruments created by pooling together a group of mortgages. These mortgages are then divided into different segments, or "tranches," which have varying levels of risk and return. Investors can choose which tranche to invest in based on their risk tolerance and investment goals. CMOs are designed to provide a steady stream of income to investors, as they receive payments from the underlying mortgages. The structure allows for more predictable cash flows, making them an attractive option for those looking to invest in the real estate market without directly owning property.