The History of Computing
The Machine That Weighed as Much as a Tank and Changed Everything
The world's first general-purpose electronic computer was programmed almost entirely by women, and for decades, almost nobody knew their names.
The Idea
When ENIAC — the Electronic Numerical Integrator and Computer — came online in 1945, it occupied 1,800 square feet of floor space, consumed enough electricity to dim the lights in an entire Philadelphia neighbourhood, and could perform roughly 5,000 additions per second. That last number sounds quaint now, but it was roughly a thousand times faster than any mechanical calculator of the era. The conceptual leap ENIAC represented wasn't just speed, though — it was programmability. Earlier machines were built to do one thing. ENIAC could be reconfigured, rewired, and repurposed. That flexibility was the seed of everything that followed. What often gets lost in the hardware mythology is how the machine actually ran. ENIAC didn't have software in any modern sense. Programming it meant physically rerouting cables and setting thousands of switches — a process that could take days. The people tasked with translating complex ballistic trajectory equations into that physical logic were six mathematicians: Jean Jennings, Frances Bilas, Betty Holberton, Ruth Lichterman, Kathleen McNulty, and Marlyn Wescoff. They were hired as 'computers' — a job title that, at the time, meant a human being who computes. They had no manual. They figured out how the machine worked by studying its blueprints and reasoned their way to a working program from first principles. What they built was, in retrospect, a form of systems thinking that would define software engineering for generations.
In the World
The ENIAC's public debut on February 15, 1946, at the University of Pennsylvania was staged as a kind of theatrical spectacle. Press photographers were invited to watch lights blink and reels spin. Army generals stood nearby looking satisfied. The six women who had spent months making the machine actually work — who had debugged it, mapped its logic, and coaxed it into computing ballistic tables — were not introduced. They stood in the crowd, watching as male engineers took questions from reporters. Decades passed. The women appeared in photographs from the era, and for years historians assumed they were models hired for publicity shots. It wasn't until the 1980s that Kathy Kleiman, then a computer science student, started asking questions about the women she kept spotting in ENIAC photos and couldn't identify. The institutions she contacted told her the women were probably just 'refrigerator ladies' — a term from the era for decorative figures placed next to machines in advertisements. Kleiman didn't accept that. After years of research, she tracked down the surviving programmers and documented their work in a film called *The Computers*. Jean Jennings Bartik, one of the six, eventually received the Computer History Museum's Fellow Award in 2008 — more than sixty years after she'd helped make computing history. She died in 2011. The delay between the doing and the recognition is its own kind of data point about who gets written into the story of innovation, and who gets edited out.
Why It Matters
ENIAC is a useful mirror to hold up against how we talk about technology today. The narrative of invention tends to collapse around individuals — a lone genius, a visionary founder, a breakthrough moment — when the actual story is almost always more distributed, more collaborative, and more contingent. The ENIAC's hardware was remarkable. But hardware without the people who reasoned through its logic would have been an expensive, blinking sculpture. There's also something clarifying about how primitive the 'revolutionary' machine actually was. The gap between ENIAC and the device you're reading this on is so vast it becomes almost philosophical. That gap closed within a single human lifetime. Understanding where computing began — what the problems actually were, what the constraints looked like, who did the thinking — gives you a more honest sense of how fast this technology has moved, and therefore a better-calibrated instinct for how much further it might go. History, in computing, is not ancient context. It's a live variable.
A Question to Ponder
When a technology is described as revolutionary, how much of that revolution was in the machine itself — and how much was in the people who figured out what to do with it?
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