December 8 – Amazing Grace

Today’s factismal: Tomorrow is Grace Hopper’s 109th birthday!

There is no doubt that women today have a tough row to hoe; they face an uphill battle in every field from psychology to medicine to particle physics. But that battle would be even more difficult if it weren’t for the efforts of women such as Rear Admiral “Amazing Grace” Hopper, who fought ignorance and sexism while also helping us to win World War II.

Grace Hopper with a UNIVAC that she taught to do COBOL (Image courtesy IBM)

Grace Hopper with a UNIVAC that she taught to do COBOL
(Image courtesy IBM)

Hopper was born on December 9, 1906, in New York City where she quickly demonstrated her aptitudes at the age of seven by taking apart alarm clocks to see how they worked. She stayed curious and kept learning, so much so that she was admitted to Vassar at the age of 17 and then to Yale, where she earned her PhD in 1934. By that time she was already a professor at Vassar, a post she would keep until the outbreak of World War II changed everything; she forced the Navy to enroll her as a midshipman (they didn’t want her because she was too small) and soon graduated at the top of her class.

At the time, the US Navy was using analog calculators to predict the tides and perform other complex calculations. And the most important of these was the Harvard Mark 1 Automatic Sequence Controlled Calculator. This 10,000 pound behemoth was 816 cubic feet of gears, cams, and cogs, powered by motors and controlled by 1,440 switches connected with 500 miles of wire that made 3,000,000 connections in the machine. And what did this mass of magnificent machinery do? After the programmers had spent the better part of a day setting up a math problem by punching holes in a paper tape, it could chug through it at the rate of six seconds for each multiplication. (If this seems slow to you, remember that the alternative was having a person do the calculation by hand on paper. When the numbers involved are 23.7890123546823 x 0.183764527829, you are willing to take a little time…)

For each new problem, a brand new paper tape had to be made with new instructions and the switches reset. But if any of the steps was wrong, then the whole tape and all of the switches had to be examined to find out which one was causing the problem. Because the commands were written only as a series of holes in paper (what we would call “ones and zeros” today), this was a tedious, painstaking affair that often took much longer than punching the original program did. It was that process, which she and others repeated thousands of times during the war, that gave her the insight of a compiler: a program that took already coded subroutines and followed a set of “ordinary language” instructions to call up the subroutines in a specific order. When her colleagues told her that such a program couldn’t be written, she did so, creating the very first compiler in 1951.

She soon developed improved versions of her compiler, relying on free copies that had been given to customers (the first open source programming!). By 1959, Hopper’s compiler was used as the basis for COBOL, one of the first and most influential computer languages. (Remember Y2K? It didn’t happen because of people who knew COBOL.) After that, Hopper went back into the Navy where she served until she retired as a commander in 1966 at the mandatory retirement age of 60.

Grace Hopper at the time of her final retirement (Image courtesy US Navy)

Grace Hopper at the time of her final retirement
(Image courtesy US Navy)

But the Navy decided that they needed her too much and waived the rules to let her come back, at which point she developed standards testing for Navy computer systems and promoted the idea of distributed computing. (Ever hear of the cloud? Yeah, that was her idea.) And she kept having great ideas until she was once again forced to retire at the age of 65. That time, the Navy only lasted six months before they asked her to come back at the rank of captain. She was soon promoted to Commodore (which became Rear Admiral) and kept in the Navy by special act of Congress until she was 79 years old. When they finally let her go, she was the oldest active-duty commissioned officer in the United States Navy.

Hopper showed the Navy and the world that women have what it takes to be the best programmers around. She led the field, even when it didn’t want to be led, and helped create the modern technological wonderland that we live in. And there is no better way to celebrate her birthday than by taking part in the Hour of Code. This tech challenge happens every year and kicks off Computer Science Week (which takes place this week in honor of Grace Hopper). At the Hour of Code, they have resources for educators, students, and citizen scientists – so there’s fun for everyone! To get started, set your browser to:

One thought on “December 8 – Amazing Grace

  1. Pingback: March 8 – A Woman’s Work | Little facts about science

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