The first programmers of ENIAC were six women nobody invited to the party.
ENIAC, unveiled in 1946, was the first programmable, electronic, general-purpose computer. There were no programming languages yet, so six women worked out how to make it compute by studying its wiring diagrams. At its grand public dedication, none of them was invited to the ceremony or the celebration dinner.
ENIAC was built at the University of Pennsylvania by John Mauchly and J. Presper Eckert for the US Army, to calculate artillery firing tables. Completed in 1945, it filled a room: about 30 metres long, more than 27 tonnes, with 18,000 vacuum tubes and around five million hand-soldered joints. It was roughly a thousand times faster than the electro-mechanical machines before it, and the press called it a 'Giant Brain'. Its first real job was not ballistics but a feasibility study for the hydrogen bomb.
Programming it meant physically setting switches and plugging cables. The job fell to six women chosen from about 200 human 'computers' who had been calculating trajectories by hand: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas and Ruth Lichterman. They studied its blueprints and circuits to understand the machine itself, and became so expert they could trace a fault to a single failed tube.
Programming was then seen as clerical work. Men with the same education were classed as professionals; the women were 'subprofessionals'. Snyder and Jennings wrote the trajectory program shown off to the public in February 1946, but none of the women was invited to the formal dedication or the dinner afterwards. For decades they were often mistaken for models posing beside the machine.
That changed thanks largely to Kathryn Kleiman, who as a computer science student discovered who the women were, and in the 1990s, learning that most had not been invited to ENIAC's 50th anniversary, set out to track them down and record their stories. In 1997 the six were inducted into the Women in Technology International Hall of Fame. ENIAC itself kept running until October 1955, when newer machines replaced it.
Source: Wikipedia — ENIAC · Text summarised from Wikipedia (CC BY-SA 4.0)
