一種人們普遍接受作為經濟交換手段的商品。它能表示價格和價值；它在人與人、國與國之間流通從而便利貿易。歷史上，很多商品曾被用作貨幣，包括貝殼、小珠、石板、牲畜等，但自17世紀起，最普通的形式是硬幣、紙幣和記帳。標準的經濟理論認為，貨幣有四種明顯的功能︰用以作為交換媒介，在商品交換和服務中普遍為人們所接受；用作衡量價值、記帳單位、實行價格制度、計算成本、利潤和虧損的一般標準；用作延期付款、放款和日後交易的計算單位；用作財富的儲存，是將不即時花費的收入保持下來的方便方法。金屬，特別是金和銀，用作貨幣至少有4,000年曆史，作為金屬貨幣流通的標準鑄幣也有2,600年的歷史。18世紀末和19世紀初，銀行開始發行可換回金銀的紙幣，成為工業經濟中主要的貨幣。第一次世界大戰中和自1930年代開始的大蕭條時期，許多國家放棄金本位制。對多數個人來説，貨幣包括鑄幣、紙幣和銀行存款。就經濟來説，總的貨幣供給比個人擁有貨幣金額定總和要大幾倍，這是因為存在金融機構的存款中大部分被貸放出去，這就是加大貨幣總供應量好幾倍。亦請參閲soft money。
money
Commodity accepted by general consent as a medium of economic exchange. It is the medium in which prices and values are expressed; it circulates from person to person and country to country, thus facilitating trade. Throughout history various commodities have been used as money, including seashells, beads, and cattle, but since the 17th century the most common forms have been metal coins, paper notes, and bookkeeping entries. In standard economic theory, money is held to have four functions: to serve as a medium of exchange universally accepted in return for goods and services; to act as a measure of value, making possible the operation of the price system and the calculation of cost, profit, and loss; to serve as a standard of deferred payments, the unit in which loans are made and future transactions are fixed; and to provide a means of storing wealth not immediately required for use. Metals, especially gold and silver, have been used for money for at least 4,000 years; standardized coins have been minted for perhaps 2,600 years. In the late 18th and early 19th century, banks began to issue notes redeemable in gold or silver, which became the principal money of industrial economies. Temporarily during World War I and permanently from the 1930s, most nations abandoned the gold standard. To most individuals today, money consists of coins, notes, and bank deposits. In terms of the economy, however, the total money supply is several times as large as the sum total of individual money holdings so defined, since most of the deposits placed in banks are loaned out, thus multiplying the money supply several times over. See also soft money.
