The document explains six management theories from the 19th and 20th centuries, each providing different frameworks for management practices. These theories include Taylor's scientific management, Weber's bureaucratic theory, von Bertalanffy's systems theory, Fayol's administrative theory, Mayo's human relations theory, and McGregor's X & Y theory, each emphasizing various aspects of employee motivation, organizational structure, and efficiency. Collectively, they offer insights into effective management styles and the importance of understanding employee dynamics.