The word personality comes from the Latin word persona, which refers to a theatrical mask taken by performers in order to project role.
It is the characteristic patterns of thoughts, feelings, and behaviors that make a person unique.
Personality is a characteristical way of thinking, feeling, and behaving.
It embraces moods, attitudes, and opinions and is most clearly expressed in
interactions with other people of group.
It also includes behavioral characteristics, both inherent and acquired,
that distinguish one person from another.
Thus we can say in short that Personality refers to individual differences in characteristic patterns of thinking, feeling and behaving.
Physiological type theories:
The idea that people fall into certain personality type categories in relation to bodily characteristics has intrigued numerous modern psychologists as well as their counterparts among the ancients. The idea that people must fall into one or another rigid personality class, however, has been largely dismissed. Two general sets of theories are considered here, the humoral and the morphological.
Morphological (body type) theories
Psychoanalytic theories
Trait theories
Galen’s theory