Technology · 1943–1947
The first electronic computers
Moore School of Electrical Engineering, University of Pennsylvania, Philadelphia (USA)
ENIAC (Electronic Numerical Integrator and Computer), built in secret for the US Army by John Mauchly and J. Presper Eckert at the University of Pennsylvania, was completed in 1945 and put to work on 10 December that year; it was the first programmable, electronic, general-purpose digital computer.
It filled a room, weighed about 27 tonnes and used about 18,000 vacuum tubes, could calculate about a thousand times faster than electromechanical machines, and was programmed with switches and cables by six women mathematicians, among them Kay McNulty, Betty Jennings and Betty Snyder. In Britain, the codebreakers at Bletchley Park had already used Colossus, a programmable electronic machine designed by Tommy Flowers, from early 1944 to read German high-command messages, though it was built for that single job and kept secret until the 1970s.
Why it mattered
Electronic computers turned calculation, and later almost all information, into something machines could process at enormous speed. The transistor, invented at Bell Labs in 1947, replaced fragile, power-hungry vacuum tubes and let computers shrink from rooms to chips; more than 13 sextillion MOS transistors had been manufactured by 2018, making them the most numerous artificial objects in history, and they run everything from phones and cars to banks, hospitals and power grids.
Elsewhere
ENIAC's first program was a study for the hydrogen bomb, not the artillery tables it was built for. Germany's Konrad Zuse had completed the electromechanical Z3 computer in Berlin in 1941.
Related
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