Barter is the process of trading products, goods or services, for other products, goods or services. It is a simple method of transaction, frequently one in which no money is exchanged. Barter systems are often utilized between nations, and sometimes between a nation and a corporation. Barter also occurs between corporations or companies and other businesses, and sometimes between a business and an individual, or two individuals. In the United States, billions of dollars worth of goods and services are exchanged each year through bartering.