Decimalisation or decimalization (see spelling differences) is the conversion of a system of currency or of weights and measures to units related by powers of 10.
Most countries have decimalised their currencies, converting them from non-decimal sub-units to a decimal system, with one basic currency unit and sub-units that are valued relative to the basic unit by a power of 10, most commonly 100 and exceptionally 1,000, and sometimes at the same time, changing the name of the currency and/or the conversion rate to the new currency.