What are the characteristics of oligopoly phenomenon?

Oligopoly is characterized by a market structure in which a small number of firms dominate the industry, leading to interdependent pricing and output decisions. Firms in an oligopoly often produce similar or differentiated products, which can result in collaborative behavior, such as price-fixing or forming cartels. High barriers to entry prevent new competitors from easily entering the market, maintaining the dominant firms' market power. Additionally, oligopolistic markets can exhibit price rigidity, where prices remain stable despite changes in demand.