A bank is an institution that accepts deposits from savers, extends loans to borrowers, and provides a range of other financial services to its customers. Banks are a central part of the modern financial system. ‘Origins and function of banking’ begins with a short history of banking before outlining the structure of a bank’s balance sheet and income statement. It goes on to describe the different types of bank and banking services provided by retail, corporate, and investment banks. It also explains the shadow banking institutions—such as hedge funds—which are not subject to the same supervisory and regulatory arrangements, and the payments system that has been transformed by the growth of computing technology.