Perfect Competition

rational free market of manufacturers and individual buyers that have all needed information (Economics)

Perfect competition is an economic model that describes a hypothetical market form in which no producer or consumer has the market power to influence prices. According to the standard economical definition of efficiency (Pareto efficiency), perfect competition would lead to a completely efficient outcome. The analysis of perfectly competitive markets provides the foundation of the theory of supply and demand.
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An idealized market environment in which every market participant is too small to affect the market price by acting on its own.

see Pure Competition.