the federal funds rate is the interest rate at which depository institutions (banks and credit unions) lend reserve balances to other depository institutions overnight, on an uncollateralized basis. Reserve balances are amounts held at the Federal Reserve to maintain depository institutions' reserve requirements. Institutions with surplus balances in their accounts lend those balances to institutions in need of larger balances.
Interbank borrowing is essentially a way for banks to quickly raise money. For example, a bank may want to finance a major industrial effort but may not have the time to wait for deposits or interest (on loan payments) to come in. In such cases the bank will quickly raise this amount from other banks at an interest rate equal to or higher than the Federal funds rate.
Raising the federal funds rate will dissuade banks from taking out such inter-bank loans, which in turn will make cash that much harder to procure. Conversely, dropping the interest rates will encourage banks to borrow money and therefore invest more freely.[5] This interest rate is used as a regulatory tool to control how freely the U.S. economy operates.
open market operations:
An open market operation (OMO) is an activity by a central bank to give (or take) liquidity in its currency to (or from) a bank or a group of banks. The central bank can either buy or sell government bonds in the open market. The usual aim of open market operations is - aside from supplying commercial banks with liquidity and sometimes taking surplus liquidity from commercial banks - to manipulate the short-term interest rate and the supply of base money in an economy, and thus indirectly control the total money supply, in effect expanding money or contracting the money supply.
Classical economic theory postulates a distinctive relationship between the supply of central bank money and short-term interest rates: like for a commodity, a higher demand for central bank money would increase its price, the interest rate. When there is an increased demand for base money, the central bank must act if it wishes to maintain the short-term interest rate. It does this by increasing the supply of base money: it goes to the open market to buy a financial asset, such as government bonds. To pay for these assets, new central bank money is generated in the seller's loro account, increasing the total amount of base money in the economy. Conversely, if the central bank sells these assets in the open market, the base money is reduced.
