This is a book about the computer revolution of the mid-twentieth century and the people who made it possible. Unlike most histories of computing, it is not a book about machines, inventors, or entrepreneurs. Instead, it tells the story of the vast but largely anonymous legions of computer specialists -- programmers, systems analysts, and other software developers -- who transformed the electronic computer from a scientific curiosity into the defining technology of the modern era. As the systems that they built became increasingly powerful and ubiquitous, these specialists became the focus...