Monetary system

A commodity money system is a monetary system in which a commodity such as gold or silver is made the unit of value and physically used as money.

One step away from commodity money is "commodity-backed money", also known as "representative money". Many currencies have consisted of bank-issued notes which have no inherent physical value, but which may be exchanged for a precious metal, such as gold. (This is known as the gold standard.)

The alternative to a commodity money system is fiat money which is defined by a central bank and government law as legal tender even if it has no intrinsic value. Originally fiat money was paper currency or base metal coinage, but in modern economies it mainly exists as data such as bank balances and records of credit or debit card purchases.

Money is mostly created, contrary to what is written in most textbooks, by banks when they loan to customers. Put simply, banks lending currency to customers creates more deposits and deficit spending. Although commercial banks create money through lending, they cannot do so freely without limit.

Central banks control the creation of money by commercial banks, by setting interest rates on reserves. This limits the amount of money the commercial banks are willing to lend, and thus create, as it affects the profitability of lending in a competitive market. This is the opposite of what many people believe about the creation of fiat money. The most common misconception was that central banks print all the money, this is not reflective of what actually happens.