Market structure refers to the organization and characteristics of a market, which influence how firms compete and set prices. It is typically categorized into four main types: perfect competition, monopolistic competition, oligopoly, and monopoly. Each type has distinct features, such as the number of firms, product differentiation, and barriers to entry. Understanding market structure is essential for analyzing economic behavior and outcomes. For instance, in a monopoly, a single firm dominates the market, leading to higher prices and less consumer choice. In contrast, perfect competition involves many firms offering identical products, resulting in lower prices and greater efficiency.