- Lecture c provided a history of computing from early counting tools like the abacus through modern computers. It described how mechanical devices that used gears evolved into electromechanical computers using relays and vacuum tubes. The first general purpose electronic computers were developed during WWII to perform calculations. Technology advanced rapidly in subsequent decades, with integrated circuits leading to smaller, faster, and less expensive computers. By the 1970s, computers were commonly used in businesses, academics, and government, including for applications like electronic medical records.