Extraversion and introversion
Extraversion and introversion are a central trait dimension in human personality theory. The terms were introduced into psychology by Carl Jung, though both the popular understanding and current psychological usage are not the same as Jung's original concept. Extraversion (also spelled extroversion) is typically associated with sociability, talkativeness, and high energy, while introversion is linked to introspection, reserve, and a preference for solitary activities. Jung defined introversion as an "attitude-type characterised by orientation in life through subjective psychic contents", and extraversion as "an attitude-type characterised by concentration of interest on the external object".
While often presented as opposite ends of a single continuum, many personality theorists, such as Carl Jung, have suggested that most individuals possesses elements of both traits, with one being more dominant.