When companies or other entities need to raise money to finance new projects, maintain ongoing operations, or refinance existing other debts, they may issue bonds directly to investors instead of obtaining loans from a bank. The company (issuer) issues a bond that contractually states the interest rate (coupon) that will be paid and the time at which the loaned funds (bond principal) must be returned (maturity date).

The issuance price of a bond is typically set at par, usually $100 or $1,000 face value per individual bond. The actual market price of a bond depends on a number of factors including the credit quality of the issuer, the length of time until expiration, and the coupon rate compared to the general interest rate environment at the time.