This report provides a comprehensive analysis of different market structures, including perfect competition, monopoly, oligopoly, and monopolistic competition. It begins by defining each market structure, detailing its key characteristics such as the number of sellers and buyers, product homogeneity, freedom of entry and exit, and information availability. The report then examines real-world examples of each structure, such as foreign exchange markets for perfect competition and British Telecom for monopoly. Furthermore, it delves into the concepts of product differentiation, non-price competition, and barriers to entry. The report also analyzes the profitability of firms within each market structure in both the short and long run, illustrating these concepts with graphical representations. Finally, it discusses the allocation of resources, comparing the productive and allocative efficiencies of perfect competition with the inefficiencies of imperfect competition. The report concludes by highlighting the implications of each market structure on market outcomes and consumer welfare.