A bond is an IOU between the issuer and the investors. An option free (straight line) bond is a simple form of bond. Straight bonds pay fixed periodic coupon (annual or semi-annual) over the life and return the principal on maturity date. For example, a bond issued by the Treasury for a par value of, say $1000, with a maturity period of five with an annual interest rate of six per cent on maturity value. In such a case, the issuer, in this case – the Treasury pays an annual interest of $60 for five years, till the bond attains a par value of $1,000 and the Treasury redeems the bond to the buyer at a value of $1000 after five years from date of issue.
Bonds can be classified as: premium bonds, par bonds, and discount bonds.
Remember that the price and yield of a bond are inversely related to each other. When yield increases, the price decreases and vice versa.