Grace Hopper

• 1. Introduction

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  Grace Hopper hung a clock on her office wall that ran counterclockwise, ticking backward through every meeting. "Humans are allergic to change," she once said. "They love to say, 'We've always done it this way.' I try to fight that. That's why I have a clock on my wall that runs counterclockwise." The clock captured a habit that ran through her whole career. Hopper was an American computer scientist, mathematician, and United States Navy rear admiral. She helped invent the idea that computers could be told what to do in plain English. That work led to COBOL, a programming language still used in business computing today. She spent decades moving between two worlds that rarely overlapped, the Navy and computer science. How did a mathematics professor end up leading programming teams from inside a naval uniform? What made her insist that ordinary words, not just symbols, belonged in computer code? And why, decades after her death, do ships, supercomputers, and even a chip architecture still carry her name?

• 2. A Curious Child at Vassar

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  At the age of seven, Grace Brewster Murray decided to find out how an alarm clock worked. She took apart seven clocks before her mother noticed, and after that she was allowed only one. Grace Brewster Murray was born in New York City on the 9th of December 1906, the eldest of three children. Her parents, Walter Fletcher Murray and Mary Campbell Van Horne, were of Scottish and Dutch descent. They attended West End Collegiate Church. Her great-grandfather, Alexander Wilson Russell, was a Navy admiral who fought at the Battle of Mobile Bay during the Civil War.

  For her preparatory schooling, Grace attended the Hartridge School in Plainfield, New Jersey. Vassar College rejected her for early admission at age sixteen because her Latin test scores were too low. She was admitted the following year and graduated Phi Beta Kappa from Vassar in 1928 with a bachelor's degree in mathematics and physics. In 1930, she earned a master's degree at Yale University.

  That same year, Grace Murray married Vincent Foster Hopper, a professor at New York University. They divorced in 1945, and she never remarried, though she kept his surname for the rest of her life. In 1934, Hopper earned a Ph.D. in mathematics from Yale under Øystein Ore. Her dissertation, titled 'New Types of Irreducibility Criteria', was published that same year. She had already begun teaching mathematics at Vassar in 1931 and was promoted to associate professor a decade later, in 1941.

  By the early 1940s, a war overseas was starting to reshape which jobs were open to a woman with a mathematics doctorate.

• 3. Fighting to Serve

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  At age thirty-four, Hopper tried to join the Navy early in World War II and was turned down. She was told she was too old to enlist, and that her weight-to-height ratio did not meet the standard. The Navy also argued that her job as a mathematics professor at Vassar was too valuable to the war effort to give up. In 1943, she obtained a leave of absence from Vassar and was sworn into the United States Navy Reserve. She was one of many women who volunteered to serve in the WAVES.

  To be commissioned, Hopper needed an exemption because she was fifteen pounds under the Navy's minimum weight of one hundred twenty pounds. She reported for duty in December and trained at the Naval Reserve Midshipmen's School at Smith College in Northampton, Massachusetts. Hopper graduated first in her class in 1944 and was assigned to the Bureau of Ships Computation Project at Harvard as a lieutenant, junior grade. There she served on the Mark I computer programming staff, headed by Howard H. Aiken.

  Hopper and Aiken co-authored three papers on the Mark I, also called the Automatic Sequence Controlled Calculator. When the war ended, her request to transfer from the WAVES into the regular Navy was denied. She was two years past the cutoff age of thirty-eight. She continued serving in the Navy Reserve and remained at the Harvard Computation Lab until 1949. There, she turned down a full professorship at Vassar to keep working as a research fellow under a Navy contract.

  Her next assignment would move her out of Harvard's labs and into a private company racing to build a new kind of computer.

• 4. Teaching Computers English

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  In 1949, Hopper joined the Eckert-Mauchly Computer Corporation as a senior mathematician and became part of the team building the UNIVAC I. She also served as UNIVAC director of Automatic Programming Development for Remington Rand, the company that later took over Eckert-Mauchly. UNIVAC became the first large-scale electronic computer sold on the market, reaching customers in 1951.

  "It's much easier for most people to write an English statement than it is to use symbols," Hopper explained. She had proposed an English-based programming language and been told flatly that computers could not understand English. "So I decided data processors ought to be able to write their programs in English, and the computers would translate them into machine code."

  By 1952, Hopper had finished a program linker, originally called a compiler, written for what was known as the A-0 System. Nobody believed her at first. "I had a running compiler and nobody would touch it," she recalled. "They told me computers could only do arithmetic." In 1954, the company named her its first director of automatic programming, and her department released early compiled languages including MATH-MATIC and FLOW-MATIC.

  In the spring of 1959, computer experts from industry and government met at a two-day conference called CODASYL, the Conference on Data Systems Languages. Hopper served as a technical consultant, and the resulting language, COBOL, extended her own FLOW-MATIC with ideas borrowed from IBM's COMTRAN. COBOL, an acronym for Common Business-Oriented Language, went on to become the most widely used business programming language of its time. Mount Holyoke alumna Jean E. Sammet was among the committee members who helped build it. From 1967 to 1977, Hopper directed the Navy Programming Languages Group and developed validation software for COBOL as part of a Navy-wide standardization program.

  In the 1970s, Hopper pushed the Defense Department to replace large centralized systems with networks of smaller, distributed computers. Under her vision, any user on any node could reach shared databases across the network. She also built standards for testing computer systems, most notably for early languages like FORTRAN and COBOL. Navy conformance tests brought the dialects of major computer vendors closer together. By the 1980s, the National Bureau of Standards, now called NIST, had taken over administering them.

  That same decade carried her through a string of Navy retirements that never quite stuck.

• 5. The Admiral Who Wouldn't Retire

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  Navy attrition regulations forced Hopper to retire from the Naval Reserve at the end of 1966, at age sixty, with the rank of commander. She was recalled to active duty in August 1967 for what was meant to be a six-month assignment; it became indefinite. She retired again in 1971, only to be asked back to active duty in 1972. In 1973, Admiral Elmo R. Zumwalt Jr. promoted her to the rank of captain.

  After Republican Representative Philip Crane saw her on a March 1983 segment of 60 Minutes, he pushed a joint resolution to promote her to commodore. The resolution was referred to the Senate Armed Services Committee but never reported out. Instead, President Ronald Reagan promoted Hopper to commodore on the 15th of December 1983, using the Appointments Clause. Effective from the 8th of November 1985, the rank of commodore was renamed rear admiral, lower half, making Hopper one of the Navy's few female admirals.

  After a career that spanned more than 42 years, Hopper retired from the Navy on the 14th of August 1986. She was, at the time, the oldest serving member of the Navy. At a retirement celebration in Boston, she received the Defense Distinguished Service Medal, the highest non-combat decoration the Department of Defense awards. At her retirement, she was the oldest active-duty commissioned officer in the Navy, at seventy-nine years, eight months, and five days old. Her retirement ceremony was held aboard the oldest commissioned ship in the United States Navy, a vessel then 188 years, nine months, and 23 days old.

  A private company was about to offer her a very different kind of job.

• 6. Life After the Navy

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  Rita Yavinsky first offered Hopper a job at Digital Equipment Corporation, but Hopper insisted on going through the normal, formal interview process anyway. In jest, she proposed a different arrangement instead. She would show up on alternating Thursdays and be exhibited at the company's computing museum as a pioneer. In exchange, she asked for a generous salary and an unlimited expense account. Instead, Digital hired her full-time as Principal Corporate Consulting Engineer, a tech-track role equivalent to senior vice president.

  At Digital, Hopper worked mainly as a goodwill ambassador, lecturing widely about the early days of computing and her own career. She visited most of the company's engineering facilities, where she generally received a standing ovation at the end of her remarks. Although she was no longer a serving officer, she always wore her Navy full dress uniform to these lectures, against official Department of Defense policy.

  "The most important thing I've accomplished, other than building the compiler," she said, "is training young people." She described her method simply. Young engineers would ask if an idea could work, and she told them to try it and backed them up. On the 22nd of November 2016, President Barack Obama posthumously awarded Hopper the Presidential Medal of Freedom.

  Hopper died in her sleep of natural causes on the 1st of January 1992, at her home in Arlington County, Virginia, at age eighty-five. She was interred with full military honors in Arlington National Cemetery.

  Away from the podium, though, stories about her working days had already made her something of a legend.

• 7. Legends from the Lecture Circuit

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  While Hopper was working on a Mark II computer at Harvard in 1947, her associates found a moth stuck in a relay, jamming the machine. They taped the moth into the log book with a note: 'First actual case of bug being found.' Neither Hopper nor her crew wrote the word 'debugging' in that log entry. Even so, the episode is remembered as an early instance of the term. Hopper is credited with popularizing 'bug' and 'debugging' in computing, though the word 'bug' had already been used for malfunctions in other fields for decades. The moth itself is still taped into the group's log book, kept at the Smithsonian's National Museum of American History in Washington, D.C.

  Audiences who came to hear her speak nicknamed her 'Grandma COBOL.' By her later career, she was in constant demand at computer-related events, known for a lively, irreverent style and a deep well of old war stories.

  Hopper handed out pieces of wire just under a foot long, 11.8 inches, the distance light travels in one nanosecond. She called these her 'nanoseconds' and used them to answer a question generals and admirals kept asking her, why satellite communication took so long. She carefully explained that the wire showed only the maximum distance a signal could travel in a vacuum, since real wires would be slower. She also used the same wire to explain why computers had to be small to be fast. She contrasted it with a 984-foot coil of wire representing a microsecond. Later, while lecturing for Digital Equipment Corporation, she switched props entirely, handing out packets of pepper and calling each ground grain a picosecond.

  Her colleague Jay Elliot once summed her up in a single image. She appeared 'all Navy,' he said, but reach inside and 'you find a Pirate dying to be released.'

  In 2013, a Google Doodle celebrated her 107th birthday with an animation of her using COBOL to print out her age. At the end, a moth flew out of the computer, a nod to the story decades earlier.

• 8. A Name Written Everywhere

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  During her lifetime, Hopper received 40 honorary degrees from universities around the world, and a college at Yale was renamed in her honor. In 1991, she received the National Medal of Technology for pioneering programming languages that opened computing to a far larger group of users. Decades earlier, in 1964, the Society of Women Engineers gave her its highest honor, the Achievement Award. She had been one of the society's founding members back in 1950. In 1973, she became the first American, and the first woman of any nationality, to be named a Distinguished Fellow of the British Computer Society.

  The U.S. Navy named a guided-missile destroyer after her, launched in 1996 and nicknamed 'Amazing Grace.' It is one of only a few American military vessels named for a woman. The National Energy Research Scientific Computing Center named its Cray XE6 supercomputer 'Hopper' in 2009, and Nvidia later named a GPU architecture 'Hopper' as well. In 2020, the U.S. Naval Academy named Hopper Hall after her, the first building at any American service academy named for a woman.

  Grace Hopper Park sits on South Joyce Street in Arlington County, Virginia, a small memorial in front of her former home, the River House Apartments. Brewster Academy in Wolfeboro, New Hampshire, dedicated its computer lab to her in 1985. She had spent childhood summers there at a family home. In 2020, Google named a new undersea cable connecting the United States, United Kingdom, and Spain 'Grace Hopper.' Completed in 2021, the cable stretches 3,900 miles.

  Since 2013, Hopper's official portrait has appeared in the matplotlib Python library as sample data, replacing the controversial Lenna image. In 2019, Time created 89 new covers to honor women of the year going back to 1920. It chose Hopper as its woman of the year for 1959. Her legacy also helped inspire the Grace Hopper Celebration of Women in Computing, an annual conference on the research and careers of women in the field.

  On the 26th of August 2024, the National Security Agency released a 90-minute talk Hopper had given in 1982. It had previously been unheard outside the room where she delivered it.