The MBTI is a psychological test designed to assist a person in identifying their personality preferences. It was developed by Katherine Briggs and her daughter Isabel Myers during World War II, and follows from the theories of Carl Jung as laid out in his work Psychological Types (1). The phrase is also a trademark of the publisher of the instrument, Consulting Psychologists Press Inc., and the trademark is registered by the Myers-Briggs Type Indicator Trust. (2) The test is frequently used in the areas of pedagogy, group dynamics, employee training, leadership training, marriage counseling, and personal development, although its value has been questioned by scientific skeptics and some psychologists.
About the test
The test differs from standardized tests and others measuring traits, such as intelligence, instead identifying preferred types. While types and traits are both inborn, traits can be improved akin to skills, whereas types, if supported by a healthy environment, naturally differentiate over time.
The test attempts to tell the order in which this occurs in each person, and it is that information, combined with interviews done with others who have indicated having the same preferences, that the complete descriptions are based on. The test then, is akin to an arrow which attempts to point in the direction of the proper description. The facet of the theory which posits that the features being tested for are in fact types, and not traits which can be improved with practice, is hotly debated, lacking definitive proof.
The types the MBTI tests for, known as dichotomies, are extraversion, introversion, sensing, intuition, thinking, feeling, judging and perceiving. Participants are given one of 16 four-letter acronyms, such as ESTJ or INFP, indicating what they prefer. The term best-fit types refers to the ethical code that facilitators are required to follow. It states that the person taking the test is always the best judge of what their preferences are, and the test itself should never be used to make this decision.
The interaction of two, three, or four preferences are known as type dynamics, and when dealing with a four-preference combination it is called a type. In total, there are 16 unique types, and many more possible two and three letter combinations, which each have their own descriptive name. Additionally, it is sometimes possible to observe the interactions that each preference combination will have with another combination, although this is more unorthodox. Complete descriptions will contain the unique interactions of all four preferences in that person, and these are typically written by licensed psychologists based on data gathered from thousands of interviews and studies. The Center for Applications of Psychological Type has released short descriptions on the internet 4. The most in-depth descriptions, including statistics, can be found in The Manual.
The above information about MBTI has been included from Wikipedia.