There are lots and lots of books written on mathematics claiming to target mass audience and containing none to minimal "mathematics". You read these kind out of books and when you turn last page, you ask yourself what was really going on all the way? Well this book is different and if you ask me, it's the best book on mathematics I've came across. It's collection of few not-too-obvious theorems derived from scratch with it's histories and uses and stories. It's the way math textbooks should have been written. And it's so good, I hate to say I've found any other book that's come even near to this one!