This is setup using the our Jungian personality test and will determine the orientation your character has in 4 key areas of psychological functions - sensation, intuition, feeling and thinking. This results in a matrix of 16 possible combinations. A ton has been written about this sort of assessment, both positive, negative. It's not a perfect test, but it is very informative and you can use it drive your character's direction or decision making. GMs will also be able to use this information when they setup situations for your character to end up in.
You can answer as few as 10 questions, but the most accurate scoring will be possible if you answer all 88 questions. There are no wrong answers and you can chose not to use this feature at all.