bank
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bank, an institution that deals in money and its substitutes and provides other money-related services. In its role as a financial intermediary, a bank accepts deposits and makes loans. It derives a profit from the difference between the costs (including interest payments) of attracting and servicing deposits and the income it receives through interest charged to borrowers or earned through securities. Many banks provide related services such as financial management and products such as mutual funds and credit cards. Some bank liabilities also serve as money—that is, as generally accepted means of payment and exchange.
This article describes the development of banking functions and institutions, the basic principles of modern banking practice, and the structure of a number of important national banking systems. Certain concepts not addressed here that are nonetheless fundamental to banking are treated in the articles accounting and money.
Principles of banking
The central practice of banking consists of borrowing and lending. As in other businesses, operations must be based on capital, but banks employ comparatively little of their own capital in relation to the total volume of their transactions. Instead banks use the funds obtained through deposits and, as a precaution, maintain capital and reserve accounts to protect against losses on their loans and investments and to provide for unanticipated cash withdrawals. Genuine banks are distinguished from other kinds of financial intermediaries by the readily transferable or “spendable” nature of at least some of their liabilities (also known as IOUs), which allows those liabilities to serve as means of exchange—that is, as money.
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Types of banks
The principal types of banks in the modern industrial world are commercial banks, which are typically private-sector profit-oriented firms, and central banks, which are public-sector institutions. Commercial banks accept deposits from the general public and make various kinds of loans (including commercial, consumer, and real-estate loans) to individuals and businesses and, in some instances, to governments. Central banks, in contrast, deal mainly with their sponsoring national governments, with commercial banks, and with each other. Besides accepting deposits from and extending credit to these clients, central banks also issue paper currency and are responsible for regulating commercial banks and national money stocks.
The term commercial bank covers institutions ranging from small neighbourhood banks to huge metropolitan institutions or multinational organizations with hundreds of branches. Although U.S. banking regulations limited the development of nationwide bank chains through most of the 20th century, legislation in 1994 easing these limitations led American commercial banks to organize along the lines of their European counterparts, which typically operated offices and bank branches in many regions.
In the United States a distinction exists between commercial banks and so-called thrift institutions, which include savings and loan associations (S&Ls), credit unions, and savings banks. Like commercial banks, thrift institutions accept deposits and fund loans, but unlike commercial banks, thrifts have traditionally focused on residential mortgage lending rather than commercial lending. The growth of a separate thrift industry in the United States was largely fostered by regulations unique to that country; these banks therefore lack a counterpart elsewhere in the world. Moreover, their influence has waned: the pervasive deregulation of American commercial banks, which originated in the wake of S&L failures during the late 1980s, weakened the competitiveness of such banks and left the future of the U.S. thrift industry in doubt.
While these and other institutions are often called banks, they do not perform all the banking functions described above and are best classified as financial intermediaries. Institutions that fall into this category include finance companies, savings banks, investment banks (which deal primarily with large business clients and are mainly concerned with underwriting and distributing new issues of corporate bonds and equity shares), trust companies, finance companies (which specialize in making risky loans and do not accept deposits), insurance companies, mutual fund companies, and home-loan banks or savings and loan associations. One particular type of commercial bank, the merchant bank (known as an investment bank in the United States), engages in investment banking activities such as advising on mergers and acquisitions. In some countries, including Germany, Switzerland, France, and Italy, so-called universal banks supply both traditional (or “narrow”) commercial banking services and various nonbank financial services such as securities underwriting and insurance. Elsewhere, regulations, long-established custom, or a combination of both have limited the extent to which commercial banks have taken part in the provision of nonbank financial services.