People have been gambling, in one form or another, for as long as history itself. Why? Money, entertainment, escape and a desire to win are all traditional explanations. Arguably, however, these are secondary considerations to a higher order purpose: a craving for control. Gambling offers a means of gaining authority over the unknown, granting us a sense of control over uncertainty. Almost always that sense is illusionary—gambling, including betting and investing, is essentially random—yet for many it is nonetheless profoundly rewarding. This book attempts to explore the reasons why. Along the way, it examines the science of probability and uncertainty, why gambling is often condemned, the difference between expectation and utility, the irrationality of human beings, evolutionary perspectives on gambling, luck and skill, market efficiency and the wisdom of crowds, why winners take all, cheating, and why the process matters more than the outcome.