A system of classification…e.g., human personality type refers to the psychological classification of different types of individuals. Personality types are sometimes distinguished from personality traits, with the latter embodying a smaller grouping of behavioral tendencies. Types are sometimes said to involve qualitative differences between people, whereas traits might be construed as quantitative differences. Commonly used type indicators in organization development are: MBTI, Firo-B, Print/Enneagram, Keirsey Temperament Sorter, 4-Di, just to name a few.