In economics, competition is the rivalry among sellers trying to achieve such goals as increasing profits, market share, and sales volume by varying the elements of the marketing mix: price, product, distribution, and promotion. Merriam-Webster defines competition in business as "the effort of two or more parties acting independently to secure the business of a third party by offering the most favorable terms." It was described by Adam Smith in The Wealth of Nations (1776) and later economists as allocating productive resources to their most highly valued uses and encouraging efficiency. Smith and other classical economists before Cournot were referring to price and non-price rivalry among producers to sell their goods on best terms by bidding of buyers, not necessarily to a large number of sellers nor to a market in final equilibrium.