A currency is a unit of exchange, facilitating the transfer of goods and services. It is a form of money, where money is defined as a medium of exchange (rather than e.g. a store of value). A currency zone is a country or region in which a specific currency is the dominant medium of exchange. To facilitate trade between currency zones, there are exchange rates i.e. prices at which currencies (and the goods and services of individual currency zones) can be exchanged against each other. Currencies can be classified as either floating currencies or fixed currencies based on their exchange rate regime. In common usage, currency sometimes refers to only paper money, as in "coins and currency", but this is misleading. Coins and paper money are both forms of currency.
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