Bond refers to a security issued by a company, financial institution or government which offers regular or fixed payment of interest in return for borrowed money for a certain period of time.

By purchasing a bond, an investor loans money for a fixed period of time at a predetermined interest rate. While the interest is paid to the bond holder at regular intervals, the principal amount is repaid at a later date, known as the maturity date. While both bonds and stocks are securities, the principle difference between the two is that bond holders are lenders, while stockholders are the owners of the organization. Another difference is that bonds usually have a defined term, or maturity, after which the bond is redeemed, whereas stocks may be outstanding indefinitely. An exception is a consol bond, which is a perpetuity (i.e., bond with no maturity).

Thus a bond is like a loan: the issuer is the borrower (debtor), the holder is the lender (creditor), and the coupon is the interest. Bonds provide the borrower with external funds to finance long-term investments, or, in the case of government bonds, to finance current expenditure. Certificates of deposit (CDs) or commercial paper are considered to be money market instruments and not bonds. Bonds must be repaid at fixed intervals over a period of time.