Mathematics can be fun for everyone, and this book shows it. It grew out of the author’s popularisation of mathematics via live, call-in TV shows and widely published articles. The questions, comments, and even the answers here come largely from the callers and readers themselves, and so the book covers the kind of mathematical problems that people are interested in, not those that professional mathematicians, writers or even publishers think people should be interested in. The book makes no attempt to fit any mould. Although written by a research mathematician, it goes where the callers and readers have directed it, over a wide range of topics and levels. Everyone paging through it will be captured by something of interest, whether they consider themselves interested in mathematics or not.