The main currency is the bookkeeping base currency, which is the basic currency in a country's circulation and is generally used as the legal price standard of the country. The minimum size of the principal currency is usually 65,438+0 monetary unit, such as 65,438+0 RMB, 65,438+0 GBP, etc. Some countries stipulate that it is an integer multiple of monetary unit, such as 10 or 100 monetary unit.

Auxiliary currency, that is, auxiliary currency, is a small amount of money below the functional currency unit, which is mainly used to assist the circulation of large denomination currency and for daily sporadic transactions or change. Generally speaking, tokens are mostly coins made of metal, and there are some paper banknotes.

In China, the primary currency refers to a single banknote with a face value of 1 yuan or 1 yuan, and the secondary currency refers to a banknote or coin with a face value of 1 yuan.