Organizational behavior (OB) is the study of how individuals and groups act within organizations. It examines how individuals' behaviors are influenced by the organization and how organizations can be designed to improve employee performance and satisfaction. OB draws from multiple disciplines including psychology, sociology, and anthropology. It aims to apply knowledge about human behavior and organizations to make organizations more effective. The document discusses the evolution of OB, key topics in OB like motivation, leadership, and organizational structure, and challenges organizations face in a changing world.