A corporate and technology history of IBM tracing its origins from nineteenth-century tabulating businesses through Thomas J. Watson Sr., the THINK culture, the Great Depression, World War II, postwar computing, System/360, the IBM Way, global expansion, antitrust battles, the personal-computer era, the 1985-1993 crisis, Lou Gerstner's turnaround, the shift toward services and software, and later transformation around cloud, analytics, and artificial intelligence.