How Personality Tests Work

Person filling out test Person filling out test
There's a good chance you've taken a personality test at some point in your life, whether it was for clinical or entertainment purposes. DragonImages/iStock/Thinkstock

Personality is generally defined as the unique patterns of thought, emotion and behavior that characterize a person, which may seem simple. But the concept of human personality isn't so straightforward — personality is complex and changeable. There are many theories on how it develops, and scientists don't really know what causes it to change. Despite the intricacy of personality, people have been trying to analyze and categorize it for more than 2,000 years. That drive to understand personality eventually gave birth to the modern personality test.

Personality tests present a series of question or ambiguous images to the test taker, each intended to help assess a person's personality. At the end of the test, all the answers are analyzed and the test taker's "type" is identified. Corporations and government agencies spend enormous amounts of money to administer personality tests, to train employees to interpret them and to use the information they provide. There are quite a few personality tests, but the most widely used is the Myers-Briggs Type Indicator (MBTI) [source: Cunningham].

Let's dig deeper to find out what it's like to take personality tests, why they're so popular (and lucrative), and what we can learn from their results.