When Darwin explained evolution he made no attempt to answer the deeper question: what is life? Even a humble bacterium accomplishes things so amazing, so dazzling, that no human engineer can match it. Life looks like magic, its secrets cloaked by a shroud of impenetrable complexity. Huge advances in biology over the past decades have served only to deepen the mystery. But now an answer to the question is at hand, and it comes from a field of science so new and fast-moving that it lacks a name, a domain where computing, chemistry, quantum physics and nanotechnology meet. The link that interweaves them is information, not in the prosaic everyday sense, but as an abstract concept as important and profound as energy. The power of information to explain life and to unify biology with physics heralds a new scientific revolution poised to transform technology and medicine, and to answer the age-old question of whether or not we are alone in the universe.