Barter is a system of trade in which one party exchanges products, goods and services in order to obtain required products, goods and services possessed by another. In a barter system, no money exchanges hands between the buyer and the seller. Instead, both parties to the sale determine how much of a product a fair trade for another product or service. Since people assign different worth to different products, a barter system makes it difficult to decide how much of an item needs to be offered for another for the transaction to become a fair trade. Barter system was largely used long ago before the world developed the concept of currency for the exchange of goods. Nevertheless, the barter system is still prevalent today among nations, corporations, companies, individuals and businesses. The barter system makes trade easier for countries that experience large volatility in currency conversion and for countries that do not have sufficient financial resources, but have large volumes of commodities that can be traded for other commodities.

Unlike one-on-one bartering, members of exchanges are not obligated to barter or purchase directly from a seller. Instead, when a barter exchange member sells a product or a service to another member, their barter account is credited for the fair market value of the sale. When a barter exchange member buys, the account is debited for the fair market value of the purchase.
The same thing holds true of all other possessions; for barter, in general, had its original beginning in nature, some men having a surplus, others too little of what was necessary for them: hence it is evident, that the selling provisions for money is not according to the natural use of things; for they were obliged to use barter for those things which they wanted; but it is plain that barter could have no place in the first, that is to say, in family society; but must have begun when the number of those who composed the community was enlarged: for the first of these had all things in common; but when they came to be separated they were obliged to exchange with each other many different things which both parties wanted.