A zero coupon bond (also discount bond or deep discount bond) is a bond in which the face value is repaid at the time of maturity. Unlike regular bonds, it does not make periodic interest payments or have so-called coupons, hence the term zero-coupon bond. When the bond reaches maturity, its investor receives its par (or face) value. Examples of zero-coupon bonds include US Treasury bills, US savings bonds, long-term zero-coupon bonds, and any type of coupon bond that has been stripped of its coupons. Zero coupon and deep discount bonds are terms that are used interchangeably. In contrast, an investor who has a regular bond receives income from coupon payments, which are made semi-annually or annually. The investor also receives the principal or face value of the investment when the bond matures. Some zero coupon bonds are inflation indexed, and the amount of money that will be paid to the bond holder is calculated to have a set amount of purchasing power, rather than a set amount of money, but most zero coupon bonds pay a set amount of money known as the face value of the bond. Zero coupon bonds may be long or short-term investments. Long-term zero coupon maturity dates typically start at ten to fifteen years. The bonds can be held until maturity or sold on secondary bond markets. Short-term zero coupon bonds generally have maturities of less than one year and are called bills. The US Treasury bill market is the most active and liquid debt market in the world. Strip bonds Zero coupon bonds have a duration equal to the bond's time to maturity, which makes them sensitive to any changes in the interest rates. Investment banks or dealers may separate coupons from the principal of coupon bonds, which is known as the residue, so that different investors may receive the principal and each of the coupon payments. That creates a supply of new zero coupon bonds. The coupons and residue are sold separately to investors. Each of the investments then pays a single lump sum. That method of creating zero coupon bonds is known as stripping, and the contracts are known as strip bonds. "STRIPS" stands for Separate Trading of Registered Interest and Principal Securities. Dealers normally purchase a block of high-quality and non-callable bonds, often government issues, to create strip bonds. A strip bond has no reinvestment risk because the payment to