Tarot cards are one of many forms of divination. They are commonly used to measure potential outcomes and evaluate influences surrounding a person, event, or both. The technical term for tarot reading is taromancy (divination through the use of tarot cards), which is a subsection of cartomancy (divination through cards in general).
Readers commonly believe that the future is fluid and thus absolute predictions of future events are impossible. Instead, they focus on possible outcomes as well as examining influences related to the issue at hand, influences the subject might not even be aware of before the reading. Tarot reading thus arms the subject with additional information so that he or she may make more informed choices.