Kurt Lewin was a German-American psychologist, widely recognized as one of the founding figures of social psychology. Born in 1890, he developed influential theories on group dynamics and organizational change. His work emphasized the importance of understanding behavior in social contexts and introduced concepts like the field theory and the change model. Lewin is best known for his three-step model of change: unfreeze, change, and refreeze. This framework helps organizations implement effective change by preparing individuals for new behaviors, facilitating the transition, and solidifying the new practices. His contributions continue to influence psychology, management, and education today.