在A-level经济学中，关于货币职能的知识有详细的解释，其将货币职能分为四种，分别是价值尺度、流通手段、贮藏手段以及支付手段。
一、价值尺度，是指货币充当衡量商品所包含价值量大小的社会尺度。货币之所以能执行价值尺度职能，是因为货币本身也具有价值，因而能以自身价值作为尺度来衡量其他商品所包含的价值量。
二、流通手段，流通手段的职能是货币作为商品交换的媒介，即购买手段的职能。其主要特点是在商品买卖中，商品的让渡和货币的让渡在同一时间内完成，通俗地说是一手交钱、一手交货。
三、贮藏手段，货币退出流通领域作为社会财富的一般代表被保存起来的职能。货币作为贮藏手段能够自发地调节流通中的货币量。当流通中需要的货币量减少时，多余的货币就退出流通；当流通中需要的货币量增加时，部分被贮存的货币就进入流通。
四、支付手段，支付手段是随着商品赊账买卖的产生而出现的。在赊销赊购中,货币被用来支付债务。后来,它又被用来支付地租、利息、税款、工资等。
We say traditionally that money has four major functions. It is a medium of exchange Whatever people usually give in exchange for the things that they buy is the medium of exchange. As we have seen, this is the function that defines money.
unit of account
The unit of account is the unit in which values are stated, recorded and settled. The differences between this and the medium of exchange may seem subtle, but there are a few cases in which the unit of account is different from the unit in which the medium of exchange is expressed. In Britain a few decades ago, Guineas were often used as the unit of account, while the medium of exchange was expressed in Pounds. Both Guineas and Pounds in turn could be expressed in shillings -- the Pound was 20 shillings and the Guinea was 21 shillings. (British currency has since been redefined).
standard of deferred payment
This is the unit in which debt contracts are stated. Deferred payment means a payment made in the future, not now. Here, again, it is usually the same as the medium of exchange, but not always. During periods of inflation, people may accept paper money for immediate payment, but insist on some other medium, such as real goods and services or gold, for deferred payment -- because the medium of exchange would lose much of its value in the meanwhile.
store of value
Again, this is something that people keep in order to maintain the value of their wealth. Again, while it would usually be the same as the medium of exchange, in inflationary times other media might be substituted, such as jewelry, land or collectable goods. In this sense, money is "set aside" for the future.
