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Grace Hopper
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Grace Hopper

TORIma Academy — Computer Scientist / Admiral

Grace Hopper

Grace Hopper

Grace Brewster Hopper ( née Murray ; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear…

Grace Brewster Hopper (née Murray; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear admiral. She is recognized as a pioneering figure in computer programming. Hopper originated the concept of machine-independent programming languages, subsequently applying this theoretical framework to the creation of FLOW-MATIC and COBOL, the latter being an early high-level programming language that remains relevant. Her contributions also include being among the initial programmers for the Harvard Mark I computer. Furthermore, she is credited with authoring the inaugural computer manual, titled "A Manual of Operation for the Automatic Sequence Controlled Calculator."

Grace Brewster Hopper (née Murray; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear admiral. She was a pioneer of computer programming. Hopper was the first to devise the theory of machine-independent programming languages, and used this theory to develop the FLOW-MATIC programming language and COBOL, an early high-level programming language still in use today. She was also one of the first programmers on the Harvard Mark I computer. She is credited with writing the first computer manual, "A Manual of Operation for the Automatic Sequence Controlled Calculator."

Prior to her naval service, Hopper obtained a Ph.D. in both mathematics and mathematical physics from Yale University, subsequently serving as a professor of mathematics at Vassar College. She resigned from her Vassar position to enlist in the United States Navy Reserve during World WarII. Her computing career commenced in 1944 as a member of the Harvard MarkI team, under the leadership of Howard H. Aiken. By 1949, she had joined the Eckert–Mauchly Computer Corporation, contributing to the team responsible for developing the UNIVAC I computer. While at Eckert–Mauchly, she oversaw the development of one of the earliest COBOL compilers.

Hopper advocated for the simplification of programming through the implementation of an English-based computer programming language. Her innovative compiler translated English terms directly into machine code, making it comprehensible to computers. By 1952, Hopper had completed her program linker (initially termed a compiler), specifically designed for the A-0 System. In 1954, Eckert–Mauchly appointed Hopper to head their automatic programming department, where she subsequently directed the release of pioneering compiled languages such as FLOW-MATIC. Her involvement in the 1959 CODASYL consortium was instrumental in the development of COBOL, a machine-independent programming language founded upon English vocabulary. Hopper actively championed the adoption of this language throughout the 1960s.

In recognition of her contributions, the U.S. Navy Arleigh Burke-class guided-missile destroyer USS Hopper bears her name, as do the Cray XE6 "Hopper" supercomputer at NERSC and the Nvidia GPU architecture "Hopper". Throughout her career, Hopper received 40 honorary degrees from international universities. A college at Yale University was subsequently renamed in her honor. In 1991, she was presented with the National Medal of Technology. On November 22, 2016, President Barack Obama posthumously conferred upon her the Presidential Medal of Freedom. In 2024, the Institute of Electrical and Electronics Engineers (IEEE) dedicated a commemorative marker at the University of Pennsylvania, honoring Grace Hopper for her pivotal role in inventing the A-0 compiler while serving as a lecturer in the School of Engineering, and acknowledging her profound inspirational impact on emerging engineers.

Early Life and Academic Background

Grace Brewster Murray was born in New York City. She was the eldest of three siblings. Her parents, Walter Fletcher Murray and Mary Campbell Van Horne, were of Scottish and Dutch ancestry and were congregants of West End Collegiate Church. Her great-grandfather, Alexander Wilson Russell, an admiral in the U.S. Navy, participated in the Battle of Mobile Bay during the Civil War.

Grace exhibited profound curiosity from childhood, a characteristic that persisted throughout her life. At seven years old, she endeavored to comprehend the mechanics of an alarm clock, disassembling seven such devices before her mother intervened, subsequently restricting her to a single clock. In her later years, she was notable for possessing a clock that operated in reverse. She elucidated this choice by stating, "Humans are resistant to change. They frequently assert, 'We have always done it this way.' I strive to challenge that mindset. Consequently, I maintain a counterclockwise-running clock on my wall." Her preparatory education was completed at the Hartridge School in Plainfield, New Jersey. Grace initially faced rejection for early admission to Vassar College at age 16 due to insufficient Latin test scores; however, she gained admission the following year. She graduated Phi Beta Kappa from Vassar in 1928, earning a bachelor's degree in mathematics and physics, and subsequently obtained her master's degree from Yale University in 1930.

In 1930, Grace Murray married Vincent Foster Hopper (1906–1976), a professor at New York University; their marriage concluded in divorce in 1945. She did not remarry, opting to retain his surname.

In 1934, Hopper completed her Ph.D. in mathematics at Yale University, supervised by Øystein Ore. Her dissertation, titled "New Types of Irreducibility Criteria," was published in the same year. She commenced her teaching career in mathematics at Vassar College in 1931, achieving promotion to associate professor by 1941.

Career

World War II

Early in World War II, Hopper attempted to secure a commission in the Navy but was initially rejected due to her age (34) exceeding the enlistment limit and an insufficient weight-to-height ratio. Furthermore, her role as a mathematician and professor at Vassar College was deemed critical to the war effort, contributing to her initial denial. Nevertheless, in 1943, she obtained a leave of absence from Vassar and was inducted into the United States Navy Reserve, joining numerous other women serving in the WAVES program.

To receive her commission, Hopper required an exemption, as her weight was 15 pounds (6.8 kg) below the Navy's minimum requirement of 120 pounds (54 kg). She reported for duty in December and underwent training at the Naval Reserve Midshipmen's School, located at Smith College in Northampton, Massachusetts. Graduating at the top of her class in 1944, Hopper was subsequently assigned to the Bureau of Ships Computation Project at Harvard University, holding the rank of lieutenant, junior grade. In this role, she became a member of the Mark I computer programming team, led by Howard H. Aiken.

Hopper and Aiken collaboratively published three papers concerning the MarkI, also recognized as the Automatic Sequence Controlled Calculator. Following the war, Hopper's application to transfer from WAVES to the regular Navy was rejected because she exceeded the age cutoff of 38 by two years. Consequently, she continued her service in the Navy Reserve. Hopper remained at the Harvard Computation Lab until 1949, declining a full professorship at Vassar College to accept a research fellowship under a Navy contract at Harvard.

UNIVAC

In 1949, Hopper joined the Eckert–Mauchly Computer Corporation as a senior mathematician, contributing to the development of the UNIVAC I. Concurrently, she held the position of UNIVAC Director of Automatic Programming Development for Remington Rand. The UNIVAC, launched in 1951, represented the first large-scale electronic computer commercially available.

Hopper advocated for the creation of a novel programming language based entirely on English words, a proposal initially met with skepticism, as she "was told very quickly that [she] couldn't do this because computers didn't understand English." Despite this opposition, she persevered, explaining, "It's much easier for most people to write an English statement than it is to use symbols." She concluded, "So I decided data processors ought to be able to write their programs in English, and the computers would translate them into machine code."

Her innovative concept faced a three-year period of non-acceptance. During this interval, she published her inaugural paper on compilers in 1952. In the early 1950s, Remington Rand acquired the company, and it was under their employment that Hopper completed her foundational work on compilers. This program was designated the A compiler, with its initial iteration being A-0.

By 1952, Hopper had developed an operational link-loader, then commonly termed a compiler. She later recounted the prevailing skepticism, stating, "Nobody believed that," and observing that despite having "a running compiler," it remained untouched because "They told me computers could only do arithmetic."

In 1954, Hopper was appointed the company's inaugural director of automatic programming. Commencing that same year, her research was significantly shaped by the Laning and Zierler system, notable as the first compiler capable of processing algebraic notation. Under her leadership, her department subsequently introduced several pioneering compiler-based programming languages, such as MATH-MATIC and FLOW-MATIC.

Hopper articulated that her A-0 compiler "translated mathematical notation into machine code." She further elaborated on the necessity of English-based programming, explaining that while "manipulating symbols was fine for mathematicians," it was impractical for data processors, who are generally not "symbol manipulators." She asserted, "Very few people are really symbol manipulators. If they are, they become professional mathematicians, not data processors." Consequently, she concluded, "It's much easier for most people to write an English statement than it is to use symbols. So I decided data processors ought to be able to write their programs in English, and the computers would translate them into machine code." This vision marked "the beginning of COBOL, a computer language for data processors," enabling users to "say 'Subtract income tax from pay' instead of trying to write that in octal code or using all kinds of symbols." She emphasized COBOL's enduring significance, stating, "COBOL is the major language used today in data processing."

COBOL

In spring 1959, a two-day Conference on Data Systems Languages (CODASYL) convened, bringing together computer specialists from both industrial and governmental sectors. Hopper functioned as a technical consultant for this committee, while numerous former members of her staff participated in the ad hoc committee responsible for establishing the new language, COBOL, an acronym for COmmon Business-Oriented Language. This novel language integrated elements from Hopper's FLOW-MATIC language with concepts derived from IBM's comparable system, COMTRAN. Hopper's conviction that programming languages should approximate natural English, rather than relying on machine code or low-level languages like assembly, was fundamentally incorporated into COBOL, which subsequently became the predominant business programming language. Jean E. Sammet, an alumna of Mount Holyoke College, was among the committee members involved in COBOL's development.

Between 1967 and 1977, Hopper held the position of director for the Navy Programming Languages Group within the Navy's Office of Information Systems Planning, achieving promotion to captain in 1973. During this tenure, she engineered validation software for COBOL and its associated compiler, contributing to a comprehensive COBOL standardization initiative across the Navy.

Standards

During the 1970s, Hopper championed the transition within the Department of Defense from extensive, centralized computing infrastructures to decentralized networks comprising smaller, distributed computers. This paradigm allowed any user at any network node to access shared databases. She was instrumental in establishing and implementing standards for evaluating computer systems and their constituent components, particularly for foundational programming languages like FORTRAN and COBOL. Naval testing for adherence to these standards fostered substantial harmonization among the programming language variations offered by leading computer manufacturers. By the 1980s, the National Bureau of Standards (NBS), now recognized as the National Institute of Standards and Technology (NIST), assumed responsibility for these tests and their formal oversight.

Retirement

Adhering to Navy attrition policies, Hopper initially retired from the Naval Reserve as a commander at the age of 60 in late 1966. However, she was recalled to active service in August 1967 for an initial six-month term, which subsequently evolved into an indefinite posting. She retired once more in 1971, only to be requested to return to active duty again in 1972. Admiral Elmo R. Zumwalt Jr. promoted her to captain in 1973.

Following Republican Representative Philip Crane's observation of Hopper on a March 1983 broadcast of 60 Minutes, he advocated for a joint resolution to elevate her to commodore on the retired list; this resolution was submitted to, but not advanced by, the Senate Armed Services Committee. Nevertheless, President Ronald Reagan promoted Hopper to commodore on December 15, 1983, utilizing the Appointments Clause. She continued her active service for several years past the mandatory retirement age, by virtue of special congressional approval. On November 8, 1985, the rank of commodore was officially redesignated as rear admiral (lower half), making Hopper one of the Navy's rare female admirals.

Concluding a distinguished career spanning over 42 years, Hopper officially retired from the Navy on August 14, 1986. At that juncture, she held the distinction of being the Navy's oldest active-duty member. During a commemorative ceremony held in Boston aboard the USS Constitution, Hopper received the Defense Distinguished Service Medal, which represents the Department of Defense's highest non-combat decoration.

Upon her retirement, she was recognized as the most senior active-duty commissioned officer in the United States Navy, at 79 years, eight months, and five days old. Her retirement ceremony was conducted aboard the oldest commissioned vessel in the United States Navy, which was then 188 years, nine months, and 23 days old.

Post-retirement

Following her retirement from naval service, Grace Hopper was appointed as a senior consultant at Digital Equipment Corporation (DEC). Initially offered a position by Rita Yavinsky, Hopper insisted on undergoing the standard formal interview process. She humorously proposed accepting a role that would require her presence only on alternating Thursdays, serving as an exhibit at their computing museum as a pioneer, in exchange for a substantial salary and an unlimited expense account. Instead, she was hired as a full-time Principal Corporate Consulting Engineer, a position equivalent to a Senior Vice President on the technical track. In this capacity, Hopper represented DEC at various industry forums, participated in numerous industry committees, and fulfilled other corporate responsibilities. She maintained this position until her death in 1992 at the age of 85.

During her tenure at DEC, Hopper primarily functioned as a goodwill ambassador. She delivered extensive lectures on the nascent stages of computing, her professional trajectory, and strategies computer vendors could implement to enhance user experience. She visited most of Digital's engineering facilities, where her remarks consistently concluded with a standing ovation. Despite no longer being a serving officer, she habitually wore her Navy full dress uniform to these lectures, a practice contrary to U.S. Department of Defense policy. In 2016, Hopper was posthumously awarded the Presidential Medal of Freedom, the nation's highest civilian honor, in recognition of her profound contributions to computer science.

Hopper articulated, "Beyond the development of the compiler, my most significant achievement lies in mentoring young individuals. They approach me, inquiring, 'Do you believe this is feasible?' My response is, 'Attempt it.' I provide them with support, as they require it. I monitor their progress as they mature, periodically encouraging them to embrace risks."

Anecdotes

Throughout a significant portion of her later career, Hopper was a highly sought-after speaker at various computer-related events. She was renowned for her dynamic and unconventional speaking style, as well as her extensive collection of early computing anecdotes. She also acquired the moniker "Grandma COBOL."

In 1947, while Grace Hopper was engaged with the Mark II Computer at Harvard University, her colleagues identified a moth lodged within a relay, which was obstructing the computer's functionality. Upon its extraction, the insect was affixed to that day's log sheet with the notation, "First actual case of bug being found." Although neither Hopper nor her team explicitly used the phrase "debugging" in their log entries, this incident is historically recognized as an early instance of "debugging" a computer, and Hopper is credited with popularizing the term within the computing field. For many decades prior to its application in computing, the term "bug" had been utilized in various fields to denote a malfunction. The preserved remains of the moth are currently taped into the group's log book at the Smithsonian Institution's National Museum of American History in Washington, D.C.

Hopper gained recognition for her distinctive nanoseconds visual aid. When individuals, including high-ranking military officers, inquired about the perceived delay in satellite communication, she would distribute pieces of wire measuring just under one foot—specifically, 11.8 inches (30 cm)—representing the distance light travels in one nanosecond. She metaphorically referred to these wire segments as "nanoseconds." Hopper meticulously clarified to her audience that the length of her "nanoseconds" represented the maximum distance signals could traverse in a vacuum within that timeframe, and that signals would propagate more slowly through the actual wires used in her demonstrations. Subsequently, she employed these same wire segments to illustrate the imperative for computers to be compact to achieve high speeds. At numerous presentations and visits, she distributed "nanoseconds" to audience members, contrasting them with a 984-foot (300-meter) coil of wire, which symbolized a microsecond. Later, while delivering these lectures during her employment at DEC, she distributed packets of pepper, designating individual grains of ground pepper as picoseconds.

Jay Elliot characterized Hopper as outwardly appearing to be "'all Navy', but when you reach inside, you find a 'Pirate' dying to be released."

Demise

On January 1, 1992, Grace Hopper passed away peacefully in her sleep from natural causes at her residence in Arlington County, Virginia, at the age of 85. She was interred with full military honors at Arlington National Cemetery.

Dates of Rank

Awards and Commendations

Military Decorations

Other Accolades

Legacy

Places

Programs

In Popular Culture

Grace Hopper Celebration of Women in Computing

Her enduring legacy served as a significant inspiration for the establishment of the Grace Hopper Celebration of Women in Computing. This annual conference is specifically structured to highlight the research and professional aspirations of women within the field of computing.

The historical context of bugs in engineering.

Notes

References

Obituary Notices

Beyer, Kurt W. (2009). Grace Hopper and the Invention of the Information Age. Cambridge, Massachusetts: MIT Press. ISBN 978-0-262-01310-9.