Barter

Barter is the trading of goods or services directly for other goods or services, without using money or any other similar unit of account or medium of exchange. The barter economy represents a primitive society's system of exchange, which historically has gradually been replaced by an exchange economy employing some form of money to facilitate trade.

An exchange system based upon a common currency is a near-absolute necessity before much economic development beyond a rather primitive tribal level can occur. This is because as societies advance, the more complex the division of labor becomes, the more finely specialized the population's productive roles, and more numerous varieties of goods and services are produced in an economy. Therefore, the more costly and cumbersome barter trading will become because of the decreased likelihood of any two people having a double coincidence of wants.