A bank is a financial institution that is a so-called "middleman" for customers and lenders. A bank acts as a payment agent, while also borrowing and lending money to the customers. Banks across the world serve as this function and other functions as well. It countries such as Japan and Germany, the banks are the primary owners of industrial corporations. The United States, however, prohibits the banks in the country to be able to own non-financial companies. The first modern bank was founded in 1406 in Genoa, Italy.

How banks work is that they act as payment agents by holding checking accounts for customers. The bank pays the checks that are drawn by the customers and they collect checks that are to be deposited into the customer's account. Banks also use other methods of payment to exchange money for its customers such as ATM machines, electronic transfers, and EFTPOS. The exchange of money in a bank is done by the bank borrowing money by accepting funds on current accounts and deposits those funds into banknotes and bonds. Banks lend money by advancing money to customers in their account, making loans, and by investing money into debt securities and other form of lending.

Banks are an important part of any economy. The banks in any given country provide nearly all payment services and is important not only to individuals, but to business and government as well. There are companies that provide banking services but are not considered a substitute for having a bank account at an established bank.

The Federal Reserve and the Federal Interest Rates are the entities that provide the data and banking rates used by the bank to write term loans for customers. These banking rates are every changing and provide consumers with additional money earned, as with interest earning bank accounts and additional money spent, as with interest rates on bank loans of all kinds.