Right now, a group of mathematicians and computer scientists are sifting through mountains of data about where we shop, who we call, and the websites we visit. Their goal? To map out our next steps and direct our behavior without our ever realizing it. In The Numerati, Stephen Baker, a 20-year veteran reporter for BusinessWeek and an Overseas Press Club Award winner, examines one of the greatest undertakings of the 21^st century and explains how the mathematical profiling of humanity will transform every aspect of modern life.