Money is any item or verifiable record that is generally accepted as payment for goods and services and repayment of debts, such as taxes, in a particular country or socio-economic context.[1][2][3] The main functions of money are distinguished as: a medium of exchange, a unit of account, a store of value and sometimes, a standard of deferred payment.[4][5] Any item or verifiable record that fulfils these functions can be considered as money.
Money is historically an emergent market phenomenon establishing a commodity money, but nearly all contemporary money systems are based on fiat money.[4] Fiat money, like any check or note of debt, is without use value as a physical commodity. It derives its value by being declared by a government to be legal tender; that is, it must be accepted as a form of payment within the boundaries of the country, for "all debts, public and private". Counterfeit money can cause good money to lose its value.