there are much longer and more detailed versions of this test out there. Susan Cain talks about Myers Briggs in her book. The test I took pegged me as an Introvert (no surprise to me since I had just previously read Quiet.)
Throughout the reading of this book, I just kept saying to myself: "So THAT is why I feel this way" or "Well, that explains this difference in how I, VS the majority of people I know approach problems, projects, interactions etc so differently" or even "Now I understand why, even though I had a great time being out with some friends last night, I feel so drained and in need of a recharge". It just explained so much to me about how the brains of introverts and extroverts work and why I always felt different around people. Like why I detest small talk but can converse for hours on some "meaty" topic. Why crowds freak me out but I can spend unnatural amounts of time by myself. Even why, as I get older, I find myself needing more and more personal space around me. This book was a real eye-opener.
If you do read it, have a highliter at the ready - there is so much you will want to mark for re-reads.