The physical form used to exchange money. For example a bank note, or coin.

Currency is a form factor agreed by all who use it to be a medium of exchange of money.


In modern times this is represented by notes and coins, while in older times it has been gold, gems and other precious commodities.


The use of notes and not gold provides a more stable currency. For example if we still used gold directly and there was a high demand for gold in industry one year, the value of the gold coins would vary dramatically. This would cause all sorts of inflationary issues.


In more recent times the need for currency has reduced due to the rise of computers as many transactions are now performed electronically.


Modern CurrencyVictorian CurrencyVictorian Currency

Chinese CurrencySpanish CurrencyRoman CurrencyAncient Currency



Further Reading

Currency (wikipedia)