Fiat money is a legal claim whose properties are backed by the law and cannot be exchanged for any other commodity. On the other hand, commodity money extracts its value from the commodity it is made. Unlike fiat money, it can be redeemed for any given commodity.
Additionally, fiat money is susceptible to government control since the government can regulate the supply of money circulating whenever they deem it fit. However, commodity money is not vulnerable to governmental manipulation since, apart from its monetary use, a commodity monetary system possesses an intrinsic value.
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