Perception involves all the ways of becoming aware of things, people, happenings or ideas.
Judgment involves all the ways of coming to conclusions about what has been perceived. If people differ systematically in what they perceive and in how they reach conclusions, then it is only reasonable for them to differ correspondingly in their reactions, interests, values, motivations, skills and interests. The MBTI is based on Jung's ideas about perception and judgment, and the attitudes in which these are used in different types of people. The aim of the MBTI is to identify the basic preferences of people in regard top perception and judgment, so that the effects of each preference, singly and combination, can be established by research and put to practical use. It is an Indicator of styles and preferences of an individual.