A bond is a contract between two people. Bonds are issued by enterprises or the government when they need to borrow money. The enterprises and the government issue bonds, which are purchased by investors. Bonds have a maturity date, and the issuer will pay the money back to the investor at a fixed rate of interest after that date. The face value of a bond, such asor can be increased or decreased depending on criteria such as the issuer's trustworthiness and the length of time for which the amount is issued.