In historic times, the introduction of currency as a standardized money facilitated a wider exchange of goods and services. NumismatistsGold served especially commonly as a form of early money, as described in "Origins of Money and of Banking" Davies, Glyn (2002). Ideas : A history of money from ancient times to the present day. University of Wales Press. ISBN 0-7083-1717-0. </ref> The circulation of a |production cost]].



