The amount of money in an economy. This may be the country’s own money, supplied by its banking system, or foreign money, used in preference to domestic money. There is no single accepted definition of what constitutes money: while notes and coin are legal tender and must be included in any definition, and bank deposits repayable on demand are unlikely to be excluded, there are various types of deposit in non-bank financial intermediaries such as building societies, and various forms of highly liquid security, which can be included or excluded in various ways. For various definitions applied in the UK see M0 to M5.