This book tells the stories of some of the great quests of mathematics, such as the centuries-long pursuit for the proof of Fermat's Last Theorem. These quests are searches for difficult-to-discover universal truths, pursued with passion not only by mathematicians and scientists, but by kings, emperors and even Jean-Luc Picard, the captain of Star Trek's Starship Enterprise. Some of their exploits are adventures as fascinating as any historical or current-day drama. The truths they have discovered help us understand not only mathematics, but also the Universe — and sometimes, ourselves.In addition to well-known quests such as Fermat's Last Theorem and the Goldbach Conjecture, some of the chapters describe more recent pursuits such as the Traveling Salesman Problem and the Multi-armed Bandit Problem. While some of the quests have been completed, others are still ongoing, and one (the Six Squares Problem) can be understood — and maybe even solved — by a five-year-old child.