Here are entered works on present-day calculators as well as on calculators and mechanical computers of pre-1945 vintage. Works on modern electronic computers first developed after 1945 are entered under Computers.
Here are entered works on electric generators, motors, transducers, sensing instruments, microphones, and similar devices, which convert electrical energy into mechanical energy, or the reverse, and which normally function as components of larger systems, e.g. electric power systems, information systems, control systems, etc.
Here are entered works on extracorporeal pumping mechanisms that duplicate the function of the natural heart. Works on intracorporeal pumping mechanisms that duplicate the function of the natural heart are entered under Heart, Artificial.