Trade
Exchange of goods and services
Trade is the act by which people swap something of value (such as products, resources, money) to obtain another valuable item. It involves the transfer of goods and services from one person or entity (seller) to another (buyer), often in exchange for money. In one modern view, trade exists due to specialization and the division of labour, a predominant form of economic activity in which individuals and groups concentrate on a small aspect of production, but use their output in trade for other products and needs.
From Wikipedia, under CC BY-SA. More on occurri.