The following summary of Myers Briggs basics comes from myersbriggs.org:
The purpose of the Myers-Briggs Type Indicator® (MBTI®)
personality inventory is to make the theory of psychological types described by
C. G. Jung understandable and useful in people's lives. The essence of the
theory is that much seemingly random variation in the behavior is actually
quite orderly and consistent, being due to basic differences in the ways
individuals prefer to use their perception and judgment.
The identification of basic preferences of each of the four
dichotomies specified or implicit in Jung's theory.
Favorite world: Do you prefer to focus on the outer world or
on your own inner world? This is called Extraversion (E) or Introversion (I).
Information: Do you prefer to focus on the basic information
you take in or do you prefer to interpret and add meaning? This is called
Sensing (S) or Intuition (N).
Decisions: When making decisions, do you prefer to first
look at logic and consistency or first look at the people and special
circumstances? This is called Thinking (T) or Feeling (F).
Structure: In dealing with the outside world, do you prefer
to get things decided or do you prefer to stay open to new information and
options? This is called Judging (J) or Perceiving (P).