The barter system is a type of trade that involves the exchange of goods and services without the use of money as a medium of exchange. Trade, on the other hand, is a broader concept that includes not just the barter system, but also, international trade, commodities trading, currency trading, etc. The main difference between barter and trade is that while barter trade does not involve money, other forms of trade occur with currency used as a medium of exchange. An important point to note is that the invention of trade whether barter or otherwise has developed a useful system under which individuals, businesses and nations can exchange or sell off the products or goods held in excess and purchase or obtain desired products, goods and services. The invention of currency has greatly simplified this process making trade convenient and fair.
Barter, the direct exchange of goods or services—without an intervening medium of exchange or money—either according to established rates of exchange or by bargaining. It is considered the oldest form of commerce. Barter is common among traditional societies, particularly in those communities with some developed form of market. Goods may be bartered within a group as well as between groups, although gift exchange probably accounts for most intragroup trade, particularly in small and relatively simple societies. Where barter and gift exchange coexist, the simple barter of ordinary household items or food is distinguished from ceremonial exchange (such as a potlatch), which serves purposes other than purely economic ones.