This engaging study traces the development of closed captioning—a field that emerged in the 1970s and 1980s from decades-long developments in cinematic subtitling, courtroom stenography, and education for the deaf. Gregory J. Downey discusses how digital computers, coupled with human mental and physical skills, made live television captioning possible. Downey's survey includess the hidden information workers who mediate between live audiovisual action and the production of visual track and written records. His work examines communication technology, human geography, and the place of labor in a technologically complex and spatially fragmented world. Illustrating the ways in which technological development grows out of government regulation, education innovation, professional profit-seeking, and social activism, this interdisciplinary study combines insights from several fields, among them the history of technology, human geography, mass communication, and information studies.