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Grace Hopper, Computer Pioneer

May 2024
3min read

Every time we call a computer glitch a bug, we should give a little nod to the “Grand Lady of Software.” Because if it wasn’t for Grace Hopper and the moth she found wedged in the hulking Mark II computer’s relay, the computer bug might have been known by any other name.

Hopper’s influence goes far beyond the bug. Hopper played such a significant part in the early history of computing that her influence, like technology itself, appears everywhere. Her resume would say she was a computer programmer—and she was—as important to the development of computers as Charles Babbage and Ada Lovelace. But her voice and vision are apparent in both technology and the way we talk about it.

Long before Apple popularized the slogan Think Different and being “disruptive” became a Silicon Valley mantra, Hopper lectured students, colleagues, and technology companies against using what she called “the most damaging phrase in the language.” What was this cardinal sin of innovation? “We’ve always done it this way.” Hopper was so adamant about banning the phrase, that she, dressed in her full navy uniform, often threatened to—poof!—”come back and haunt” the poor souls who dared to utter the phrase. In any case, the idea has remained a core tenet of technology. Today, the worst thing you can say about a new idea is that it’s safe. As a constant reminder to rethink even those things we consider fundamental, Hopper’s office clock ticked counterclockwise.

“It’s always easier to ask forgiveness than it is to get per-mission” is another well-known Hopperism—and one she practiced long before fine-tuning its expression. When Hopper was a child, she was powerfully drawn to gadgets. At age seven, she wanted to know how an alarm clock roused her family out of bed each morning. So Hopper took the thing apart. When she couldn’t put it back together again, she dismantled another one.

Still stumped, she tried another. When she’d pulled the screws and springs from seven machines, Hopper’s mother made a deal with the child: she could tinker with one.

Supported by a mathematics-loving mother and an encouraging father, Hopper started at Vassar at age seventeen, earning a degree in mathematics in 1928. From there she went to Yale, knocking out both a master’s and a PhD in mathematics (the school’s first woman to do so) before returning to Vassar to teach math, the subject she loved.

For Hopper, everything changed when Japan bombed Pearl Harbor in 1941. Hopper, at age thirty-four, wanted to do something tangible for her country; she wanted to enlist. Sure, the
government thought that her vocation as a math professor was too important to leave. Sure, she was sixteen pounds underweight and, by average enlistment standards, very old. But Hopper was confident and determined. She wrangled a leave of absence from Vassar, arranged a waiver for her weight, and in December 1943 succeeded in joining the US Naval Reserve.

In the Reserve, Hopper was assigned a post in the Bureau of Ships Computation Project at Harvard University. Her reputation as an excellent mathematician preceded her. As she arrived, her supervisor offered the kind of pleasantries that come after a long, impatient wait: “Where have you been?” He immediately put her to work on the organization’s massive Mark I computer, charging her with learning “how to program the beast and to get a program running.”
For a mathematician with a gadget obsession, the Mark I—at 51-feet-long and 5 tons—was a dream with a staggering processing rate: some 72 words and three operations calculated every second. Hopper was its lead programmer, its tour guide.

The 561-page manual she wrote for the machine was groundbreaking, according to a computer historian. “The instruction sequences . . . are thus among the earliest examples anywhere of digital computer programs.”

After she was released from active duty, Hopper chose not to return to Vassar. She had ornery computers to wrestle, and she was just having too much fun.

In 1949, Hopper moved to the Eckert-Mauchly Computer Corporation in Philadelphia, where she helped design the first electronic digital computer for large-scale commercial use. She also returned to what she’d identified as a problem with programming: it was very specialized and very dull. At the time, programmers had to manually enter every 1 and 0. What the human/machine interface needed was a sort of translator, a program that would take reasonable human commands and transform them into the binary language of computers. Never the type to wait to have things done for her, Hopper designed one. Her program A-0, which stands for automatic programming language zero, is now known as the first “compiler.” 

In the history of programming languages, adding the ability both to interact with the machine more intuitively and to pack more into a command was hugely significant. Instead of having to input strings of l’s and 0’s to explain to the computer what it needed to do, Hopper condensed those strings into, say, one letter on a keyboard.

She also provided the foundation for COBOL (common business oriented language), a programming language designed specifically for business use. Even today, COBOL remains a major player in business and government organizations.

In 1966, Hopper retired from the Naval Reserve. It didn’t last long. Her presence was requested for a six-month stint to work on Automatic Data Processing, at which point the navy made it clear that her services would be required indefinitely. Hopper was promoted to captain and then, in 1977, made the special advisor to the commander of the Naval Data Automation Command. During her second stint in the navy—one that lasted nineteen years post-“retirement”—she helped set common standards for the organization’s programming languages. Those standards made their way to the Department of Defense and then into all of our computers.

When Hopper, smoking unfiltered Lucky Strikes, strolled confidently down a conference hall corridor with a group trailing behind her, people routinely turned in awe. At the podium, she was a captivating visionary, exciting listeners with predictions about the future of computers and challenging the audience to think more creatively.

Once, when she was asked about the boundaries of a technology, she replied, “They’ll only be limited if our imaginations are limited. It’s all up to us. Remember, there were people who said the airplane couldn’t fly.”

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