What is Myers-Bigg's?
The Myers-Briggs Type Indicator (MBTI) is a personality questionnaire designed to identify certain psychological differences according to the typological theories of Carl Gustav Jung, as published in his 1921 book Psychological Types (English edition, 1923). The original developers of the indicator were Katharine Cook Briggs and her daughter, Isabel Briggs Myers. They began developing the indicator during World War II.
The 4 personality combinations types out of 16 different personalities:
ISFJ ( Protector )
INTJ ( Mastermind)
ENTJ (Field Marshal)
See what's your personality by taking this Myer's Brigg indicator test: http://www.humanmetrics.com/cgi-win/JTypes2.asp