Grace Brewster Hopper (born Murray; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear admiral. She was a pioneer in computer programming. Hopper developed the idea for programming languages that work on different computers. She used this idea to create the FLOW-MATIC programming language and COBOL, an early high-level programming language still used today. She was also one of the first programmers to work on the Harvard Mark I computer. She wrote the first computer manual, titled "A Manual of Operation for the Automatic Sequence Controlled Calculator."

Before joining the Navy, Hopper earned a Ph.D. in mathematics and mathematical physics from Yale University. She was a professor of mathematics at Vassar College. She left her job at Vassar to join the United States Navy Reserve during World War II. Hopper began her computing career in 1944 as part of the Harvard Mark I team, which was led by Howard H. Aiken. In 1949, she joined the Eckert–Mauchly Computer Corporation and worked on the team that developed the UNIVAC I computer. At Eckert–Mauchly, she managed the development of one of the first COBOL compilers.

Hopper believed programming should use an English-based language. Her compiler translated English words into machine code that computers could understand. By 1952, she completed her program linker (originally called a compiler), which was designed for the A-0 System. In 1954, Eckert–Mauchly chose Hopper to lead their department for automatic programming. She oversaw the release of early compiled languages like FLOW-MATIC. In 1959, she helped create COBOL, a machine-independent programming language based on English words, as part of the CODASYL consortium. She promoted the use of COBOL throughout the 1960s.

The U.S. Navy Arleigh Burke-class guided-missile destroyer USS Hopper was named in her honor, as was the Cray XE6 "Hopper" supercomputer at NERSC and the Nvidia GPU architecture "Hopper." During her lifetime, Hopper received 40 honorary degrees from universities worldwide. A college at Yale University was renamed in her honor. In 1991, she was awarded the National Medal of Technology. On November 22, 2016, she was posthumously awarded the Presidential Medal of Freedom by President Barack Obama. In 2024, the Institute of Electrical and Electronics Engineers (IEEE) placed a marker at the University of Pennsylvania to honor Grace Hopper for inventing the A-0 compiler during her time as a lecturer in the School of Engineering. The marker recognizes her influence on young engineers.

Early life and education

Grace Brewster Murray was born in New York City. She was the oldest of three children. Her parents, Walter Fletcher Murray and Mary Campbell Van Horne, had Scottish and Dutch ancestors and attended West End Collegiate Church. Her great-grandfather, Alexander Wilson Russell, was an admiral in the US Navy who fought in the Battle of Mobile Bay during the Civil War.

Grace was very curious as a child, and this interest lasted her entire life. At age seven, she wanted to learn how an alarm clock worked. She took apart seven alarm clocks before her mother discovered what she was doing. After that, she was allowed to use only one clock. Later in life, she kept a clock that ran backward. She explained, "Humans are allergic to change. 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."

For her early education, Grace attended the Hartridge School in Plainfield, New Jersey. She was not accepted for early admission to Vassar College at age 16 because her Latin test scores were too low. However, she was admitted the following year. She graduated Phi Beta Kappa from Vassar in 1928 with a bachelor's degree in mathematics and physics. She earned her master's degree from Yale University in 1930.

In 1930, Grace Murray married Vincent Foster Hopper, a professor at New York University. They divorced in 1945. She did not marry again and kept his surname.

In 1934, Hopper earned a Ph.D. in mathematics from Yale University under the guidance of Øystein Ore. Her dissertation, "New Types of Irreducibility Criteria," was published that year. She began teaching mathematics at Vassar in 1931 and was promoted to associate professor in 1941.

Career

Grace Hopper tried to join the Navy early in World War II but was denied. At age 34, she was too old to enlist, and her weight-to-height ratio was too low. She was also denied because her job as a mathematician and math professor at Vassar College was valuable to the war effort. During the war in 1943, Hopper took a leave of absence from Vassar and joined the United States Navy Reserve. She was one of many women who volunteered to serve in the WAVES.

She needed special permission to join the Navy because she was 15 pounds (6.8 kg) below the Navy’s minimum weight of 120 pounds (54 kg). She joined the Navy 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 University as a lieutenant, junior grade. She worked on the Mark I computer programming staff led by Howard H. Aiken.

Hopper and Aiken co-authored three papers on the Mark I, also known as the Automatic Sequence Controlled Calculator. Her request to transfer to the regular Navy, instead of the WAVES, was denied at the end of the war because she was two years older than the cutoff age of 38. She continued serving in the Navy Reserve. Hopper stayed at the Harvard Computation Lab until 1949, choosing to work as a research fellow under a Navy contract at Harvard instead of accepting a full professorship at Vassar.

In 1949, Hopper became an employee of the Eckert–Mauchly Computer Corporation as a senior mathematician and joined the team developing the UNIVAC I. She later served as UNIVAC director of Automatic Programming Development for Remington Rand. The UNIVAC was the first large-scale electronic computer available for sale in 1951.

When Hopper suggested creating a programming language that used English words, she was told that computers could not understand English. She argued that writing in English was easier for most people than using symbols. She believed that computers should translate English statements into machine code.

Her idea was not accepted for three years. During that time, she published her first paper on compilers in 1952. In the early 1950s, the company was taken over by Remington Rand, and her original compiler work was completed while she worked for them. The program was called the A compiler, and its first version was A-0.

In 1952, Hopper created an operational link-loader, which was called a compiler at the time. She later said that no one believed her work, as people thought computers could only perform arithmetic.

In 1954, Hopper became the company’s first director of automatic programming. Her work was influenced by the Laning and Zierler system, the first compiler to accept algebraic notation as input. Her department developed some of the first compiler-based programming languages, including MATH-MATIC and FLOW-MATIC.

Hopper explained that her A-0 compiler translated mathematical notation into machine code. She believed that writing programs in English was easier for most people than using symbols. This idea led to the creation of COBOL, a computer language for data processors. COBOL allowed users to write statements like "Subtract income tax from pay" instead of using complex symbols. COBOL became the most widely used business language.

In 1959, computer experts from industry and government met in a two-day conference called the Conference on Data Systems Languages (CODASYL). Hopper served as a technical consultant, and many of her former employees worked on the committee that defined COBOL. COBOL combined ideas from her FLOW-MATIC language and IBM’s COMTRAN. The language was designed to be close to English, making it easier for data processors to use.

From 1967 to 1977, Hopper served as the director of the Navy Programming Languages Group in the Navy’s Office of Information Systems Planning. She was promoted to the rank of captain in 1973. She developed validation software for COBOL and its compiler as part of a Navy program to standardize COBOL.

In the 1970s, Hopper supported the Defense Department’s plan to replace large, centralized computer systems with networks of small, distributed computers. Users on any computer could access shared databases on the network. She developed standards for testing computer systems and components, especially for early programming languages like FORTRAN and COBOL. Navy tests for these standards helped unify programming language versions across major computer companies. In the 1980s, these tests were managed by the National Bureau of Standards (NBS), now known as the National Institute of Standards and Technology (NIST).

Retirement

In accordance with Navy rules about leaving the Navy, Hopper retired from the Naval Reserve with the rank of commander at age 60 at the end of 1966. She was called back to active duty in August 1967 for a six-month job that became an indefinite assignment. She retired again in 1971 but was asked to return to active duty in 1972. In 1973, she was promoted to captain by Admiral Elmo R. Zumwalt Jr.

After Republican Representative Philip Crane saw her on a March 1983 episode of 60 Minutes, he supported a proposal to promote Hopper to commodore on the retired list. The proposal was sent to the Senate Armed Services Committee but was not moved forward. Instead, President Ronald Reagan used the Appointments Clause to promote her to commodore on December 15, 1983. She stayed on active duty for several years past the required retirement age with special approval from Congress. On November 8, 1985, the rank of commodore was renamed rear admiral (lower half), making Hopper one of the Navy’s few female admirals.

After a career lasting more than 42 years, Hopper retired from the Navy on August 14, 1986. At that time, she was the oldest serving member of the Navy. A celebration was held in Boston on the USS Constitution to honor her retirement, where she received the Defense Distinguished Service Medal, the highest non-combat award given by the Department of Defense.

At the time of her retirement, she was the oldest active-duty commissioned officer in the United States Navy (79 years, eight months, and five days), and her retirement ceremony took place on the oldest commissioned ship in the United States Navy (188 years, nine months, and 23 days).

Post-retirement

After retiring from the Navy, Grace Hopper was hired as a senior advisor by Digital Equipment Corporation (DEC). She was first offered a job by Rita Yavinsky, but she asked to go through the usual formal interview process. She jokingly suggested she would accept a job that allowed her to work on alternating Thursdays, while being displayed in DEC's computing museum as a pioneer, in exchange for a high salary and unlimited travel funds. Instead, she was hired as a full-time Principal Corporate Consulting Engineer, a high-level position similar to a senior vice president in technology. In this role, she represented the company at industry events, joined committees, and completed other tasks. She held this position until her death at age 85 in 1992.

At DEC, Hopper mainly worked as a representative for the company. She gave many talks about the early days of computing, her career, and ways computer companies could help their users. She visited most of DEC's engineering centers, where she often received loud applause after her speeches. Even though she was no longer in the military, she always wore her Navy uniform during these talks, even though it was against U.S. Department of Defense rules. In 2016, Hopper was awarded the Presidential Medal of Freedom, the highest honor given to civilians in the United States, for her work in computer science.

"The most important thing I've accomplished, other than creating the compiler," she said, "is teaching young people. They come to me and ask, 'Do you think we can do this?' I tell them, 'Try it.' I support them. They need that. I keep track of them as they grow and encourage them to take risks at regular times so they don't forget to be brave."

Anecdotes

Grace Hopper was often invited to speak at events related to computers during the later part of her career. She was famous for her energetic and humorous speaking style, as well as the many stories she shared about her early work during wartime. She was also known by the nickname "Grandma COBOL."

In 1947, while working on a Mark II Computer at Harvard University, Hopper and her team found a moth trapped inside a relay, which was blocking the computer’s operation. The insect was carefully removed and noted in a logbook with the message, "First actual case of bug being found." Although Hopper and her team did not use the word "debugging" in their records, this event is considered one of the earliest examples of fixing a computer problem, a process now called "debugging." Hopper is credited with helping to popularize the term "bug" to describe computer malfunctions. The term "bug" had already been used in other fields before being applied to computers. Today, the preserved moth is displayed in a logbook at the Smithsonian Institution’s National Museum of American History in Washington, D.C.

Hopper became well-known for using a simple visual aid to explain the speed of signals. When asked why satellite communication was slow, she handed out short wires that were just under one foot long—11.8 inches (30 cm)—the distance light travels in one nanosecond. She called these wires "nanoseconds." She explained that this length represented the maximum distance signals could travel in a vacuum in one nanosecond, but that signals moved more slowly through actual wires. Later, she used the same wires to show why computers needed to be small to operate quickly. At her talks, she often gave out "nanoseconds" to the audience and compared them to a much longer coil of wire—984 feet (300 meters)—which represented a microsecond. While working for DEC, she also used packets of ground pepper, calling the individual grains "picoseconds."

Jay Elliot described Hopper as appearing to be "all Navy," but when you look closer, you find a "Pirate" eager to be discovered.

Death

On January 1, 1992, Hopper passed away peacefully in her sleep due to natural causes at her home in Arlington County, Virginia. She was 85 years old at the time of her death. She was buried with full military honors in Arlington National Cemetery.

Awards and honors

• 1964: Hopper received the Society of Women Engineers Achievement Award, the Society’s highest honor, "for her important work in the growing computer industry as an engineering manager and creator of automatic programming systems." In May 1950, Hopper was one of the founding members of the Society of Women Engineers.
• 1969: Hopper received the first Data Processing Management Association Man of the Year award (now called the Distinguished Information Sciences Award).
• 1971: The annual Grace Murray Hopper Award for Outstanding Young Computer Professionals was created by the Association for Computing Machinery.
• 1973: Hopper was elected to the U.S. National Academy of Engineering.
• 1973: She became the first American and the first woman of any nationality to be named a Distinguished Fellow of the British Computer Society.
• 1981: Hopper received an Honorary PhD from Clarkson University.
• 1982: Hopper received the American Association of University Women Achievement Award and an honorary Doctor of Science from Marquette University.
• 1983: Hopper received the Golden Plate Award from the American Academy of Achievement.
• 1985: Hopper received an Honorary Doctor of Science from Wright State University and an Honorary Doctor of Letters from Western New England College (now Western New England University).
• 1986: Hopper received the Defense Distinguished Service Medal at her retirement and an honorary Doctor of Science from Syracuse University.
• 1987: Hopper became the first recipient of the Computer History Museum Fellow Award "for contributions to the development of programming languages, for standardization efforts, and for lifelong naval service."
• 1988: Hopper received the Golden Gavel Award from Toastmasters International.
• 1991: Hopper received the National Medal of Technology "for her pioneering work in developing computer programming languages that simplified computer technology and made it easier for more people to use computers." She was also elected a Fellow of the American Academy of Arts and Sciences.
• 1992: The Society of Women Engineers created three annual, renewable "Admiral Grace Murray Hopper Scholarships."
• 1994: Hopper was inducted into the National Women’s Hall of Fame.
• 1996: The USS Hopper (DDG-70) was launched. Nicknamed "Amazing Grace," it is one of the few U.S. military ships named after women.
• 2001: Eavan Boland wrote a poem titled "Code," dedicated to Grace Hopper, in her 2001 collection Against Love Poetry. The Government Technology Leadership Award, called "The Gracies," was also named in her honor.
• 2009: The Department of Energy’s National Energy Research Scientific Computing Center named its flagship system "Hopper." The Office of Naval Intelligence created the Grace Hopper Information Services Center.
• 2013: Google created a Google Doodle for Hopper’s 107th birthday, showing her sitting at a computer, using COBOL to print her age. At the end, a moth flies out of the computer.
• 2016: On November 22, 2016, Hopper was posthumously awarded the Presidential Medal of Freedom for her work in computer science.
• 2017: Hopper College at Yale University was named in her honor.
• 2021: The Admiral Grace Hopper Award was established by the chancellor of the College of Information and Cyberspace (CIC) of the National Defense University to recognize leaders in information and cybersecurity within the National Security community.

Legacy

• Grace Hopper received 40 honorary degrees from universities worldwide during her lifetime.
• Nvidia named its 2024 CPU generation "Grace" and its GPU generation "Hopper" in her honor.
• The Navy's Hopper Information Services Center is named for her.
• The Navy named a guided-missile destroyer "Hopper" after her.
• In 2019, Time magazine created 89 new covers to celebrate women of the year starting from 1920; it chose Hopper for 1959.
• On June 30, 2021, a satellite named "Grace" (also called ÑuSat 20, COSPAR 2021-059AU) was launched into space.
• On August 26, 2024, the NSA released a 90-minute talk from 1982 by Hopper in two parts.

• Grace Hopper Avenue in Monterey, California, is home to the Navy's Fleet Numerical Meteorology and Oceanography Center and the National Weather Service's San Francisco Bay Area forecast office.
• The Grace M. Hopper Navy Regional Data Automation Center is located at Naval Air Station, North Island, California.
• Grace Murray Hopper Park, on South Joyce Street in Arlington County, Virginia, is a small memorial park in front of her former residence (River House Apartments) and is now owned by Arlington County.
• Brewster Academy, a school in Wolfeboro, New Hampshire, dedicated its computer lab to her in 1985, calling it the Grace Murray Hopper Center for Computer Learning. The academy also awards a Grace Murray Hopper Prize to graduates who excel in computer systems. Hopper spent her childhood summers at a family home in Wolfeboro.
• Grace Hopper College is one of the residential colleges at Yale University.
• An administration building at Naval Support Activity Annapolis (formerly Naval Station Annapolis) in Maryland is named the Grace Hopper Building in her honor.
• In 2020, Hopper Hall became the U.S. Naval Academy's academic building for its cyber science department, and it is the first building at any service academy to be named after a woman.
• The U.S. Naval Academy also owns a Cray XC-30 supercomputer named "Grace," hosted at the University of Maryland-College Park.
• Building 1482 at Naval Air Station North Island, housing the Naval Computer and Telecommunication Station San Diego, is named the Grace Hopper Building and contains the History of Naval Communications Museum.
• Building 6007, C2/CNT West at Aberdeen Proving Ground, Maryland, is named after her.
• Grace Hopper Lane is the name of a street outside the Nathan Deal Georgia Cyber Innovation and Training Center in Augusta, Georgia.
• Grace Hopper Academy is a for-profit immersive programming school in New York City named in her honor. It opened in January 2016 with the goal of increasing the number of women in software engineering careers.
• A bridge over Goose Creek, connecting the north and south sides of Naval Support Activity Charleston at Joint Base Charleston, South Carolina, is named the Grace Hopper Memorial Bridge in her honor.
• Minor planet 5773 Hopper, discovered by Eleanor Helin, is named in her honor. The official naming was published by the Minor Planet Center on November 8, 2019 (M.P.C. 117229).
• Grace Hopper Hall, a community meeting hall in Orlando, Florida, is named for her and is located on the site of the former Orlando Naval Training Center.
• The U.S. Naval Academy dedicated Hopper Hall, its cyber, computer science, and computer engineering building, to Rear Admiral Hopper in 2020. The building opened to midshipmen in the spring of 2021.

• Women at Microsoft Corporation formed an employee group called "Hoppers" and established a scholarship in her honor.
• Since 2015, one of the nine competition fields at the FIRST Robotics Competition world championship has been named for Hopper.
• A named professorship in the Department of Computer Sciences at Yale University was established in her honor. Joan Feigenbaum was named to this position in 2008.
• In 2020, Google named its new undersea network cable "Grace Hopper." The cable connects the U.S., UK, and Spain and was completed in 2021, stretching 3,900 miles.

• In Gene Luen Yang's comic book series Secret Coders, the main character is named Hopper Gracie-Hu.
• Since 2013, Hopper's official portrait has been used in the matplotlib Python library as a sample image, replacing the previously used Lenna image.

Her legacy inspired the creation of the Grace Hopper Celebration of Women in Computing. This annual conference highlights the research and career interests of women in computing.

Obituary notices

• Betts, Mitch by Computerworld volume 26, page 14, 1992
• Bromberg, Howard by IEEE Software volume 9, pages 103–104, 1992
• Danca, Richard A. by Federal Computer Week volume 6, pages 26–27, 1992
• Hancock, Bill by Digital Review volume 9, page 40, 1992
• Power, Kevin by Government Computer News volume 11, page 70, 1992
• Sammet, J. E. by Communications of the ACM volume 35 (4), pages 128–131, 1992
• Weiss, Eric A. by IEEE Annals of the History of Computing volume 14, pages 56–58, 1992