The MBTI assessment uses a questionnaire to determine how people perceive the world and make decisions and groups people into 16 personality types.
DISC is an assessment tool developed by Dr. William Moulton Marston at Harvard in 1928. It is an objective way to look at behaviors.
The Myers-Briggs Type Indicator breaks personalities down into 16 types and here are the best memes to better help you understand them.
The AVA measures 4 personalities: aggressiveness, sociability, emotional control, social adaptability, and is often used as an employment test.