The term "
computer", in use from the mid 17th century, meant "one who computes": a person performing mathematical
calculationA calculation is a deliberate process for transforming one or more inputs into one or more results, with variable change.The term is used in a variety of senses, from the very definite arithmetical calculation of using an algorithm to the vague heuristics of calculating a strategy in a competition...
s, before
electronic computersA computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
became commercially available.
Teams of people were frequently used to undertake long and often tedious calculations; the work was divided so that this could be done in parallel.
Since the end of the 20th century, the term "human computer" has also been applied to individuals with prodigious powers of mental arithmetic, also known as
mental calculatorMental calculators are people with a prodigious ability in some area of mental calculation, such as multiplying large numbers or factoring large numbers...
s.
Origins in astronomy
The approach was taken for
astronomicalAstronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
and other complex calculations. Perhaps the first example of organized human computing was by the Frenchman Alexis Claude Clairaut (1713–1765), when he divided the computation to determine timing of the return of Halley's Comet with two colleagues, Joseph Lalande and
Nicole-Reine LepauteNicole-Reine Lepaute, née Étable , was a French astronomer and mathematician. She predicted the return of Halley's Comet, calculated the timing of a solar eclipse and constructed a group of catalogs for the stars...
. For some men being a computer was a temporary position until they moved on to greater advancements. For women the occupation was generally closed, but this changed in the late 19th century with
Edward Charles PickeringEdward Charles Pickering was an American astronomer and physicist, brother of William Henry Pickering.Along with Carl Vogel, Pickering discovered the first spectroscopic binary stars. He wrote Elements of Physical Manipulations .Pickering attended Boston Latin School, and received his B.S. from...
. His group was at times termed "
Pickering's HaremEdward Charles Pickering decided to hire women as skilled workers to process astronomical data. Among these women were Williamina Fleming, Annie Jump Cannon, Henrietta Swan Leavitt and Antonia Maury. This staff came to be known as "Pickering's Harem" or, more respectfully, as the Harvard Computers...
." Many of the women astronomers from this era are computers with possibly the best known being
Henrietta Swan LeavittHenrietta Swan Leavitt was an American astronomer. A graduate of Radcliffe College, Leavitt went to work in 1893 at the Harvard College Observatory in a menial capacity as a "computer", assigned to count images on photographic plates...
. Florence Cushman was one of the
Harvard UniversityHarvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
computers from 1888 onward. Among her best known works for him was
A Catalogue of 16,300 Stars Observed with the 12-inch Meridian Photometer. She also worked with
Annie Jump CannonAnnie Jump Cannon was an American astronomer whose cataloging work was instrumental in the development of contemporary stellar classification. With Edward C...
. That said, as a female computer she normally earned half of what a male counterpart would.
The
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
n mathematician
Radhanath SikdarRadhanath Sikdar was an Indian mathematician who, among many other things, calculated the height of Peak XV in the Himalaya and showed it to be the tallest mountain above sea level. Peak XV was later named Mount Everest.-Early life:Radhanath was born as youngest child of Tituram, a resident of...
was employed as a "computer" for the
Great Trigonometric SurveyThe Great Trigonometric Survey was a project of the Survey of India throughout most of the 19th century. It was piloted in its initial stages by William Lambton, and later by George Everest. Among the many accomplishments of the Survey were the demarcation of the British territories in India and...
of India in 1840. It was he who first identified and calculated the height of the world's highest mountain, later called
Mount EverestMount Everest is the world's highest mountain, with a peak at above sea level. It is located in the Mahalangur section of the Himalayas. The international boundary runs across the precise summit point...
.
Wartime computing and the invention of electronic computing
Human computers have played integral roles in the
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
war effortIn politics and military planning, a war effort refers to a coordinated mobilization of society's resources—both industrial and human—towards the support of a military force...
in the
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
, and because of the depletion of the male labor force due to the
draftConscription in the United States has been employed several times, usually during war but also during the nominal peace of the Cold War...
, many computers during
World War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
were women, frequently with degrees in
mathematicsMathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...
. In the
Manhattan ProjectThe Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
, human computers, working with a variety of mechanical aids, assisted numerical studies of the complex formulas related to
nuclear fissionIn nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...
. Because the six people responsible for setting up problems on the
ENIACENIAC was the first general-purpose electronic computer. It was a Turing-complete digital computer capable of being reprogrammed to solve a full range of computing problems....
(the premiere general-purpose electronic digital computer built at the
University of PennsylvaniaThe University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution...
during World War II) were drafted from a corps of human computers, the world's first professional computer programmers were women, paving the way for careers in
data processingComputer data processing is any process that a computer program does to enter data and summarise, analyse or otherwise convert data into usable information. The process may be automated and run on a computer. It involves recording, analysing, sorting, summarising, calculating, disseminating and...
as socially acceptable for women in an era of gender roles. These six computers-turned-computer-programmers were
Kay McNultyKathleen "Kay" McNulty Mauchly Antonelli was one of the six original programmers of the ENIAC, the first general-purpose electronic digital computer.-Early life and education:...
,
Betty SnyderFrances Elizabeth "Betty" Holberton was one of the six original programmers of ENIAC, the first general-purpose electronic digital computer.-Early life and education:...
,
Marlyn WescoffMarlyn Meltzer was one of the original programmers for the ENIAC computer.She was born Marlyn Wescoff and graduated from Temple University in 1942. She was hired by the Moore School of Engineering later that year to perform weather calculations, mainly because she knew how to operate an adding...
,
Ruth LichtermanRuth Teitelbaum was one of the original programmers for the ENIAC computer.Teitelbaum graduated from Hunter College with a B.Sc. in Mathematics...
,
Betty Jean JenningsJean Bartik was one of the original programmers for the ENIAC computer.She was born Betty Jean Jennings in Gentry County, Missouri, in 1924 and attended Northwest Missouri State Teachers College, majoring in mathematics. In 1945, she was hired by the University of Pennsylvania to work for Army...
, and
Fran BilasFrances Spence was one of the original programmers for the ENIAC computer.She was born Frances Bilas in Philadelphia in 1922. She attended Temple University but then was awarded a scholarship to Chestnut Hill College. She majored in mathematics with a minor in physics and graduated in 1942...
.
Following World War II, the
NACAThe National Advisory Committee for Aeronautics was a U.S. federal agency founded on March 3, 1915 to undertake, promote, and institutionalize aeronautical research. On October 1, 1958 the agency was dissolved, and its assets and personnel transferred to the newly created National Aeronautics and...
used human computers in flight research to transcribe raw data from celluloid film and
oscillographAn oscillograph is an instrument for measuring alternating or varying electric current in terms of current and voltage. There are two instruments that are in common use today:*Electromagnetic oscillograph*Cathode-ray oscilloscope...
paper and then, using
slide ruleThe slide rule, also known colloquially as a slipstick, is a mechanical analog computer. The slide rule is used primarily for multiplication and division, and also for functions such as roots, logarithms and trigonometry, but is not normally used for addition or subtraction.Slide rules come in a...
s and electric
calculatorAn electronic calculator is a small, portable, usually inexpensive electronic device used to perform the basic operations of arithmetic. Modern calculators are more portable than most computers, though most PDAs are comparable in size to handheld calculators.The first solid-state electronic...
s, reduce it to standard engineering units.
External links