information:classification, linguistic:paraphrasing
Supply and demand

In capitalist economic structures, supply and demand is an economic model of price determination in a market. It postulates that in a perfectly competitive market, the unit price for a particular good will vary until it settles at a point where the quantity demanded by consumers (at the current price) will equal the quantity supplied by producers (at the current price), resulting in an economic equilibrium for price and quantity.

The "basic laws" of supply and demand, as described by David Besanko and Ronald Braeutigam, are the following four: