When the U.S. Army unveiled ENIAC in 1946, the press photos showed a wall of vacuum tubes and a room full of men in suits standing proudly beside their creation. The machine was described as the greatest computing device ever built, weighing thirty tons, consuming fifteen kilowatts of power, and solving ballistic calculations in seconds that would have taken humans days. But there was one detail left out of every press release, every photograph, every headline. The people who actually made ENIAC work were six women whose names did not appear anywhere on the official documentation.

Their names were Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Meltzer, Fran Bilas, and Ruth Lichterman. They had been hired as “computers,” which at the time meant human beings who performed mathematical calculations by hand. When ENIAC was being assembled at the University of Pennsylvania’s Moore School in 1945, the engineers who designed it assumed that programming would be a simple matter of wiring the machine to perform pre-set functions. They did not anticipate that the machine would need to be taught, step by step, how to solve problems it had never been explicitly wired to handle. That job fell to the six women.

The work was brutally difficult. There were no programming languages. There were no compilers. There was no debug mode. The women sat on the floor of the ENIAC room for hours at a time, tracing electrical signals through hundreds of switches and cables, figuring out how to make the machine perform arithmetic operations by manipulating its physical configuration. They had to understand the machine’s architecture better than most of the engineers who built it, because they were the only ones thinking about what the machine needed to do rather than how it was constructed. Kay McNulty later described the process as learning a new language without a dictionary.

The Eratosthenes sieve algorithm, which finds prime numbers, had to be implemented by routing electrical signals through the machine’s accumulators and multipliers in a specific sequence. The women figured this out through trial and error, sitting cross-legged on the carpeted floor of a room that was warm from the vacuum tubes and dimly lit because the Army wanted to keep the machine classified. They documented nothing formally. When ENIAC was publicly demonstrated in February 1946, the press described it as a triumph of engineering design, not programming ingenuity. The six women were mentioned in a single sentence buried in a two-paragraph article in the Philadelphia Inquirer.

This pattern of erasure repeats itself across technological history with almost mechanical regularity. Ada Lovelace gets called the first programmer while the men who built Babbage’s machines are described as engineers, even though both groups did essentially the same work. Grace Hopper gets her own programming language named after her while the thousands of women who wrote COBOL code in factories and banks across America remain anonymous. The story of the Apollo moon landing centers on Neil Armstrong and Buzz Aldrin while Margaret Hamilton’s team, who wrote the flight software that actually kept the module from crashing, is reduced to a footnote about “support staff.”

The reason this erasure keeps happening is not malice so much as it is a habit of storytelling. We prefer narratives with clear heroes: the lone inventor in the garage, the visionary CEO on stage, the brilliant engineer at the whiteboard. These stories are clean and satisfying. They fit into keynote presentations and biographical documentaries. The reality of technology is messier. It involves teams of people doing unglamorous work under constraints that nobody outside the room understands. It involves women sitting on floors routing cables because no one thought programming was a discipline worth documenting. It involves systems that reward visibility over substance.

I think about this every time I read a tech blog post that attributes a breakthrough to a single founder or engineer. The pattern is so familiar now that it barely registers as distortion anymore. We have internalized the idea that technological progress moves through identifiable individuals rather than through collective effort, and this shapes how we hire, promote, and credit people in our own work. When you tell stories that erase invisible labor, you create a world where invisible labor continues to be erased.

The six ENIAC programmers were finally recognized in 1997, fifty-one years after the machine was unveiled. They received an invitation to the Computer History Museum’s inaugural Induction Ceremony, and by then most of them were in their seventies and eighties. Three of them attended. The other three had died. It was a belated acknowledgment that the people who made the first electronic computer actually work deserved their names attached to the story, but it also highlighted how much time passes before systems correct their own blind spots.

What the ENIAC programmers teach us is not just about historical accuracy. It is about how we choose to tell stories about progress, and what those choices reveal about who we think deserves credit. The vacuum tubes that made ENIAC famous have been dust and rust for decades. The women who taught it to compute are mostly gone too. But the pattern they expose, the habit of crediting the visible while ignoring the essential, is still running in every organization that tells its own origin story without mentioning the people who actually did the work.