For you what is the most useful book you ever read in your life and why?

For me is the code of the extraordinary mind by Vishen Lakhiani, this book is about personal development and is the best one I ever read in the field and has more useful information for you to apply immediately in your life than any other book.
As a quick summary: In this book you will learn one of the most important aspects of the world, that generally you don't ever choose what you truly want from life but normally what your family and culture pass to you, in this book you start to see where in your beliefs about life there are what the author calls brules(bulshit rules ex: money is the only key to happiness) then your learn how to spot them and how to destroy their influence in your life, you will also learn how to think like a nonconformist and how to build your future and present in the way you truly want to live