Retirement investment annuities are financial products that provide a steady stream of income to individuals during their retirement years. An ANNUITY is a contract between an individual and an insurance company, in which the individual pays a lump sum or makes periodic payments in exchange for a guaranteed stream of income over a specified period of time. Annuities can be used to supplement other retirement income sources such as Social Security, pensions, and investments. They can also provide a hedge against inflation and help protect against outliving one's savings.