Early and Historical Computing Machines

Early and historical computing machines are the mechanical, electromechanical and first-generation electronic devices that established the foundations of modern computer engineering before the transistor-based computer became the norm. The class spans hand-cranked and motor-driven adding machines built for bookkeeping and accounting, electronic calculators that replaced mechanical gear trains with solid-state arithmetic circuits, and the earliest general-purpose electronic computers such as the vacuum-tube machines built to solve large numerical problems during and after the Second World War. These devices are grouped together because each one mechanized arithmetic and computation with the technology available at its own moment in engineering history, tracing the path from a geared desktop machine to a room-sized electronic computer to the integrated circuit.