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Grace Hopper is not just the name of the latest NVIDIA AI processor, GH200. It is also the name of one of the founders of modern computer systems. She and Ada Lovelace are credited as two of the most influential women in the early evolution of the computer industry. They both foresaw the value of programming, while many focused solely on the hardware.
In addition to contributing to the advancement of computer science, as Walter Isaacson described her, she was “the most colorful programming pioneer, a gutsy and spirited, yet also charming and collegial, naval officer.” She retired from the Navy as a rear admiral in 1986.
On August 19, 1982, she presented this talk at the NSA which was recorded and released just last year, where she told many of the stories she is famous for. I selected six vignettes that are relevant today and highlighted how perceptive her vision was, 42 years later. The transcript of this presentation can be found here.
The Value of Information
The focus of her talk was on the value of information. She saw very clearly the future. “Two things are clear: more and more data will be generated, and all of it will be online and accessible instantly.”
Not all information is of equal value, and some of the data that gets into our database is incorrect. She warned of the danger of focusing too much on the quantity of information we collect and not on its quality. “We don’t know the cost of incorrect information in the system. What are we willing to spend to make the information more accurate?”
Ask Forgiveness
“I have very important advice for young people: Go ahead and do it. It’s much easier to apologize than it is to get permission.” She goes on to say, “I could turn into the most helpless female you ever saw. Gee, I'm sorry, I didn’t know I couldn’t do that.”
In interviews, she was often asked what accounted for her success as a woman in the male-dominated Navy and computer world. She would always respond with a phrase that applies equally well to most of us.
A corollary to this phrase is what she told all the sailors under her command. She forbade them to ever use the phrase, “But we’ve always done it that way.” She would say, "When you present a new idea, never accept the first no, or the second no."
There is no reason a clock has to run clockwise. It would work just as well rotating counterclockwise. It would still be an effective clock if the hands stood still and the numbers rotated.
As a result of her style, she said, “I'm an extraordinarily annoying employee. I normally drive all of my bosses totally nuts, because I won't do anything until I understand what I've been told to do. So, when you tell me to do something, I start asking questions, until I get a clear picture of what I've been told to do.”
What is a Nanosecond?
When she started out with the Harvard Mark 1 computer in 1944, it could perform two addition steps in 300 milliseconds. She had to learn what a millisecond (msec) was. As the processing speed advanced, she had to learn what a microsecond was, and then a nanosecond.
Hopper says “Well, that really had me on the ropes, because in the first place I didn't know what a billion was, and I don't think most of those guys up in Washington do either! And if you don't know what a billion is, how on Earth do you know what a billionth is? I fussed and fumed. Finally, one morning, in total desperation, I called over to the Engineering building and I said, "Please cut off a nanosecond and send it over to me."
From then on, she would carry a 12-in. long string as a reminder to tell everyone this is a nanosecond (nsec), and give them out to every computer user she met. Figure 1 shows her holding a nsec.
To emphasize her point, she would also carry around a microsecond, which seems like forever in comparison. Figure 2 illustrates Grace Hopper holding a microsecond.
Figure 2. Grace Hopper holding a microsecond. Her follow-up for describing a psec is “The best way to make picoseconds is to get one of those big pepper grinders, and you can make picoseconds all over the table.”
Parallel Processing
Even though the first microprocessor had been introduced only a few years earlier, she recognized the limitations of scaling a single processor's performance and the value of parallel processing.
“Now, back in the early days of this country, when they moved heavy objects around, they didn't have any Caterpillar tractors, they didn't have any big cranes. They used oxen. And when they got a great big log on the ground, and one ox couldn't budge the darn thing, they did not try to grow a bigger ox. They used two oxen. And I think they’re trying to tell us something. When we need greater computer power, the answer is not to get a bigger computer—it's to get another computer.”
The First Computer Bug
Right after the war, she was working on the Harvard Mark II computer. “We were building Mark II the summer of 1945. It was a hot summer in Cambridge, and naturally, since it was World War II, we were working in a World War I temporary building. The air conditioning wasn't very good, there were no screens, and the Mark II stopped. We finally located the failing relay. It was one of the big signal relays and inside the relay, beaten to death by the relay contacts, was a moth. So the operator got a pair of tweezers and very carefully fished the moth out of the relay, put it in the log book, put Scotch tape over and below it, he wrote. First actual bug found”. A copy of the logbook preserved in the Smithsonian Institution is shown in Figure 3.
After this incident, Grace Hopper popularized the term "computer bug" and debugging as the literal removal of bugs from a computer.
Final Words of Wisdom
In her closing remarks, she noted how bright young kids were and our responsibility to them. “You manage things, you lead people. The one thing young people are looking for is good, positive leadership.”
Her wisdom in so many areas applies today just as well as it did back when she spoke in 1982. For more information on her technical contributions, check out this fascinating PhD thesis, "What Would Grace Hopper Do? Reclaiming Women's Place in Computer Science"? by Kristin Isaacson.