The discount rate is the interest rate charged to banks by the Federal Reserve. There are actually three different "discount rates" - one for each of the Fed's discount window programs: primary credit, secondary credit, and seasonal credit, each with its own interest rate. However, "the discount rate" usually refers to the interest rate charged for primary credit
Under the primary credit program, loans are extended for a very short term (usually overnight) to depository institutions in generally sound financial condition. Depository institutions that are not eligible for primary credit may apply for secondary credit to meet short-term liquidity needs or to resolve severe financial difficulties. Seasonal credit is extended to relatively small depository institutions that have recurring intra-year fluctuations in funding needs, such as banks in agricultural or seasonal resort communities.
The discount rate charged for primary credit (the primary credit rate) is set above the usual level of short-term market interest rates. The discount rate on secondary credit is above the rate on primary credit. The discount rate for seasonal credit is an average of selected market rates. Discount rates are established by each Reserve Bank's board of directors, subject to the review and determination of the Board of Governors of the Federal Reserve System. The discount rates for the three lending programs are the same across all Reserve Banks except on days around a change in the rate.