The disadvantage of using barter is that it depends on the mutual coincidence of needs. Before any transaction will be undertaken, the needs of one person must mirror the needs of another person. If you have an surplus of goats and need more wheat, you must find someone that has a surplus of wheat and needs more goats. To overcome this mutual coincidence problem, intermediaries developed that would store, trade, and warehouse commodities.
See also: Economics, Business, Marketing, Local currency, International trade, Hyperinflation. List of international trade topics