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In financial economics, a financial institution acts as an agent that provides financial services for its clients. Financial institutions generally fall under financial regulation from a government authority. Common types of financial institutions include banks, building societies, credit unions, stock brokerages, asset management firms, and similar businesses.
Financial institutions provide a service as intermediaries of the capital and debt markets. They are responsible for transferring funds from investors to companies, in need of those funds. The presence of financial institutions facilitate the flow of monies through the economy. To do so, savings accounts are pooled to mitigate the risk brought by individual account holders in order to provide funds for loans. Such is the primary means for depository institutions to develop revenue. Should the yield curve become inverse, firms in this arena will offer additional fee-generating services including securities underwriting, sales & trading, and prime brokerage.

A bank is a commercial or state institution that provides financial services , including issuing money in various forms, receiving deposits of money, lending money and processing transactions and the creating of credit. A commercial bank accepts deposits from customers and in turn makes loans, even in excess of the deposits; a process known as fractional-reserve banking. Some banks (called Banks of issue) issue banknotes as legal tender. Many banks offer ancillary financial services to make additional profit; for example, most banks also rent safe deposit boxes in their branches.
Currently in most jurisdictions commercial banks are regulated and require permission to operate. Operational authority is granted by bank regulatory authorities which provides rights to conduct the most fundamental banking services such as accepting deposits and making loans. A commercial bank is usually defined as an institution that both accepts deposits and makes loans; there are also financial institutions that provide selected banking services without meeting the legal definition of a bank.

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ratan