This document discusses the nature and origins of money. It defines money as a medium of exchange, unit of account, and store of value. Money emerged spontaneously through indirect exchange to overcome the problem of barter's double coincidence of wants. Commodities like salt, cattle, and metals historically served as money. Banks play a role in money creation by issuing money substitutes in the form of deposits and loans. Under fiat money systems, governments have more control over money than commodity standards, which placed natural limits on their ability to influence the money supply.