This is a list of amateur mathematicians—people whose primary vocation did not involve mathematics (or any similar discipline) yet made notable, and sometimes important, contributions to the field of mathematics. *

Ahmes Ahmes ( egy, jꜥḥ-ms “, a common Egyptian name also transliterated Ahmose) was an ancient Egyptian scribe who lived towards the end of the Fifteenth Dynasty (and of the Second Intermediate Period) and the beginning of the Eighteenth Dyna ...

(scribe) *

Ashutosh Mukherjee Sir Ashutosh Mukherjee (anglicised, originally Asutosh Mukhopadhyay, also anglicised to Asutosh Mookerjee) (29 June 1864 – 25 May 1924) was a prolific Bengali educator, jurist, barrister and mathematician. He was the first student to be awar ...

(lawyer) *

Robert Ammann Robert Ammann (October 1, 1946 – May, 1994) was an amateur mathematician who made several significant and groundbreaking contributions to the theory of quasicrystals and aperiodic tilings. Ammann attended Brandeis University, but generally did ...

(programmer and postal worker) *

John Arbuthnot John Arbuthnot FRS (''baptised'' 29 April 1667 – 27 February 1735), often known simply as Dr Arbuthnot, was a Scottish physician, satirist and polymath in London. He is best remembered for his contributions to mathematics, his membersh ...

(surgeon and author) *

Jean-Robert Argand Jean-Robert Argand (, , ; July 18, 1768 – August 13, 1822) was an amateur mathematician. In 1806, while managing a bookstore in Paris, he published the idea of geometrical interpretation of complex numbers known as the Argand diagram and is known ...

(shopkeeper) *

Leon Bankoff Leon Bankoff (December 13, 1908 – February 16, 1997), born in New York City, New York, was an American dentist. As an amateur mathematician he constructed the Bankoff circle. He was also an Esperantist. Life After a visit to the City ...

(Beverly Hills dentist) * Rev. Thomas Bayes (Presbyterian minister) *

Andrew Beal Daniel Andrew Beal (born November 29, 1952) is an American banker, businessman, investor, and amateur mathematician. He is a Dallas-based businessman who accumulated wealth in real estate and banking. Born and reared in Lansing, Michigan, Beal i ...

(businessman) *

Isaac Beeckman Isaac Beeckman (10 December 1588van Berkel, p10 – 19 May 1637) was a Dutch philosopher and scientist, who, through his studies and contact with leading natural philosophers, may have "virtually given birth to modern atomism".Harold J. Cook, in ...

(candlemaker) *

Chester Ittner Bliss Chester Ittner Bliss (February 1, 1899 – March 14, 1979) was primarily a biologist, who is best known for his contributions to statistics. He was born in Springfield, Ohio in 1899 and died in 1979. He was the first secretary of the International ...

(biologist) *

Napoléon Bonaparte Napoleon Bonaparte ; it, Napoleone Bonaparte, ; co, Napulione Buonaparte. (born Napoleone Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French military commander and political leader who ...

(general) *

Mary Everest Boole Mary Everest Boole (11 March 1832 in Wickwar, Gloucestershire – 17 May 1916 in Middlesex, England) was a self-taught mathematician who is best known as an author of didactic works on mathematics, such as ''Philosophy and Fun of Algebra'', an ...

(homemaker, librarian) * William Bourne (innkeeper) *

Nathaniel Bowditch Nathaniel Bowditch (March 26, 1773 – March 16, 1838) was an early American mathematician remembered for his work on ocean navigation. He is often credited as the founder of modern maritime navigation; his book '' The New American Practical Navi ...

(indentured bookkeeper) *

Achille Brocot Louis Achille Brocot (pronounced "broco") (11 July 1817 – 19 January 1878) was a French clockmaker. and amateur mathematician.. He is known for his discovery (contemporaneously with, but independently of, German number theorist Moritz Stern) of ...

(clockmaker) *

Jost Bürgi Jost Bürgi (also ''Joost, Jobst''; Latinisation of names, Latinized surname ''Burgius'' or ''Byrgius''; 28 February 1552 – 31 January 1632), active primarily at the courts in Kassel and Prague, was a Swiss clockmaker, a maker of astronomica ...

(clockmaker) *

Marvin Ray Burns The MRB constant is a mathematical constant, with decimal expansion . The constant is named after its discoverer, Marvin Ray Burns, who published his discovery of the constant in 1999. Burns had initially called the constant "rc" for root constant ...

(veteran) *

Gerolamo Cardano Gerolamo Cardano (; also Girolamo or Geronimo; french: link=no, Jérôme Cardan; la, Hieronymus Cardanus; 24 September 1501– 21 September 1576) was an Italian polymath, whose interests and proficiencies ranged through those of mathematician, ...

(medical doctor) * D. G. Champernowne (college student) *

Thomas Clausen Thomas Clausen may refer to: * Thomas Clausen (educator) (1939–2002), educator from Baton Rouge, Louisiana *Thomas Clausen (musician) (born 1949), Danish jazz pianist *Thomas Clausen (mathematician) Thomas Clausen (16 January 1801, Snogbæk, ...

(technical assistant) * Sir James Cockle (judge) *

Federico Commandino Federico Commandino (1509 – 5 September 1575) was an Italian humanist and mathematician. Born in Urbino, he studied at Padua and at Ferrara, where he received his doctorate in medicine. He was most famous for his central role as translator o ...

(medical doctor) * Herb Conn (rock climber) *

William Crabtree William Crabtree (1610–1644) was an astronomer, mathematician, and merchant from Broughton, then in the Hundred of Salford, Lancashire, England. He was one of only two people to observe and record the first predicted transit of Venus in 16 ...

(merchant) *

Nathan Daboll Nathan Daboll ( – March 9, 1818) was an American teacher who wrote the mathematics textbook most commonly used in American schools in the first half of the 19th century. During the course of his career, he also operated a popular navigation sch ...

(cooper) *

Felix Delastelle Felix may refer to: * Felix (name), people and fictional characters with the name Places * Arabia Felix is the ancient Latin name of Yemen * Felix, Spain, a municipality of the province Almería, in the autonomous community of Andalusia, ...

(bonded warehouseman) *

Martin Demaine Martin L. (Marty) Demaine (born 1942) is an artist and mathematician, the Angelika and Barton Weller artist in residence at the Massachusetts Institute of Technology (MIT). Demaine attended Medford High School in Medford, Massachusetts. After st ...

(goldsmith and glass artist) * Humphry Ditton (minister) *

Harvey Dubner Harvey Dubner (1928–2019) was an electrical engineer and mathematician who lived in New Jersey, noted for his contributions to finding large prime numbers. In 1984, he and his son Robert collaborated in developing the 'Dubner cruncher', a board ...

(engineer) *

Henry Dudeney Henry Ernest Dudeney (10 April 1857 – 23 April 1930) was an English author and mathematician who specialised in logic puzzles and mathematical games. He is known as one of the country's foremost creators of mathematical puzzles. Early life ...

(civil servant) *

Albrecht Dürer Albrecht Dürer (; ; hu, Ajtósi Adalbert; 21 May 1471 – 6 April 1528),Müller, Peter O. (1993) ''Substantiv-Derivation in Den Schriften Albrecht Dürers'', Walter de Gruyter. . sometimes spelled in English as Durer (without an umlaut) or Due ...

(painter) *

M. C. Escher Maurits Cornelis Escher (; 17 June 1898 – 27 March 1972) was a Dutch graphic artist who made mathematically inspired woodcuts, lithographs, and mezzotints. Despite wide popular interest, Escher was for most of his life neglected in t ...

(graphic artist) *

John Ernest John Ernest (May 6, 1922 – July 21, 1994) was an American-born constructivist abstract artist. He was born in Philadelphia, in 1922. After living and working in Sweden and Paris from 1946 to 1951, he moved to London, England, where he lived and w ...

(painter) *

Pasquale Joseph Federico Pasquale ("Pat") Joseph Federico (March 25, 1902 – January 2, 1982) was a lifelong mathematician and longtime high-ranking official of the United States Patent Office. Biography He was born in Monessen, Pennsylvania. About 1910 the family moved t ...

(patent attorney) *

Pierre de Fermat Pierre de Fermat (; between 31 October and 6 December 1607 – 12 January 1665) was a French mathematician who is given credit for early developments that led to infinitesimal calculus, including his technique of adequality. In particular, he ...

(lawyer) *

Sarah Flannery Sarah Flannery (born 1982, County Cork, Ireland) was, at sixteen years old, the winner of the 1999 Esat Young Scientist Exhibition for her development of the Cayley–Purser algorithm, based on work she had done with researchers at Baltimore T ...

(high school student) *

Reo Fortune Reo Franklin Fortune (27 March 1903 – 25 November 1979) was a New Zealand-born social anthropologist. Originally trained as a psychologist, Fortune was a student of some of the major theorists of British and American social anthropology i ...

(anthropologist) *

John G.F. Francis John G.F. Francis (born 1934) is an English computer scientist, who in 1961 published the QR algorithm for computing the eigenvalues and eigenvectors of matrices, which has been named as one of the ten most important algorithms of the twentieth ...

(research assistant) *

Benjamin Franklin Benjamin Franklin ( April 17, 1790) was an American polymath who was active as a writer, scientist, inventor, statesman, diplomat, printer, publisher, and political philosopher. Encyclopædia Britannica, Wood, 2021 Among the leading inte ...

(printer and diplomat) * Bernard Frenicle de Bessy *

Gemma Frisius Gemma Frisius (; born Jemme Reinerszoon; December 9, 1508 – May 25, 1555) was a Frisian physician, mathematician, cartographer, philosopher, and instrument maker. He created important globes, improved the mathematical instruments of his d ...

(medical doctor) *

Britney Gallivan The discipline of origami or paper folding has received a considerable amount of mathematics, mathematical study. Fields of interest include a given paper model's flat-foldability (whether the model can be flattened without damaging it), and the u ...

(high school student) *

James Garfield James Abram Garfield (November 19, 1831 – September 19, 1881) was the 20th president of the United States, serving from March 4, 1881 until his death six months latertwo months after he was shot by an assassin. A lawyer and Civil War gene ...

(United States President) * Antoine Gombaud (essayist) *

Thorold Gosset John Herbert de Paz Thorold Gosset (16 October 1869 – December 1962) was an English lawyer and an amateur mathematician. In mathematics, he is noted for discovering and classifying the semiregular polytopes in dimensions four and higher, and ...

(lawyer) *

Jørgen Pedersen Gram Jørgen Pedersen Gram (27 June 1850 – 29 April 1916) was a Danish actuary and mathematician who was born in Nustrup, Duchy of Schleswig, Denmark and died in Copenhagen, Denmark. Important papers of his include ''On series expansions determin ...

(actuary) *

Hermann Grassmann Hermann Günther Grassmann (german: link=no, Graßmann, ; 15 April 1809 – 26 September 1877) was a German polymath known in his day as a linguist and now also as a mathematician. He was also a physicist, general scholar, and publisher. His mat ...

(school teacher) *

John Graunt John Graunt (24 April 1620 – 18 April 1674) has been regarded as the founder of demography. Graunt was one of the first demographers, and perhaps the first epidemiologist, though by profession he was a haberdasher. He was bankrupted later in li ...

(haberdasher) * George Green (miller) *

Aubrey de Grey Aubrey David Nicholas Jasper de Grey (; born 20 April 1963) is an English author and biomedical gerontologist. He is the author of ''The Mitochondrial Free Radical Theory of Aging'' (1999) and co-author of ''Ending Aging'' (2007). He is known ...

(gerontologist) *

André-Michel Guerry André-Michel Guerry (; December 24, 1802 – April 9, 1866) was a French lawyer and amateur statistician. Together with Adolphe Quetelet he may be regarded as the founder of moral statistics which led to the development of criminology, soci ...

(lawyer) *

Charles James Hargreave Charles James Hargreave (4 December 1820 – 23 April 1866) was an England, English judge and mathematician. Life The eldest son of James Hargreave, woollen manufacturer, he was born at Wortley, West Yorkshire, Wortley, Leeds, Yorkshire, in D ...

(judge) *

Oliver Heaviside Oliver Heaviside FRS (; 18 May 1850 – 3 February 1925) was an English self-taught mathematician and physicist who invented a new technique for solving differential equations (equivalent to the Laplace transform), independently developed vec ...

(telegraph operator) *

Kurt Heegner Kurt Heegner (; 16 December 1893 – 2 February 1965) was a German private scholar from Berlin, who specialized in radio engineering and mathematics. He is famous for his mathematical discoveries in number theory and, in particular, the Stark–He ...

(private scholar) *

John R. Hendricks John Robert Hendricks (September 4, 1929 – July 7, 2007) was a Canadian amateur mathematician specializing in magic squares and magic hypercube, hypercubes. He published many articles in the Journal of Recreational Mathematics as well as other ...

(meteorologist) * Anthony Hill (painter) *

Paul Jaccard Paul Jaccard (18 November 1868 in Sainte-Croix, Switzerland, Sainte-Croix – 9 May 1944 in Zurich) was a professor of botany and plant physiology at the ETH Zurich. He studied at the University of Lausanne and ETH Zurich (PhD 1894). He continued s ...

(botanist) *

Alfred Bray Kempe Sir Alfred Bray Kempe FRS (6 July 1849 – 21 April 1922) was a mathematician best known for his work on linkages and the four colour theorem. Biography Kempe was the son of the Rector of St James's Church, Piccadilly, the Rev. John Edward K ...

(lawyer) *

Thomas Kirkman Thomas Penyngton Kirkman FRS (31 March 1806 – 3 February 1895) was a British mathematician and ordained minister of the Church of England. Despite being primarily a churchman, he maintained an active interest in research-level mathematics, a ...

(church rector) *

Laurence Monroe Klauber Laurence Monroe Klauber (December 21, 1883 in San Diego, California – May 8, 1968), was an American herpetology, herpetologist and the foremost authority on rattlesnakes. He was the first curator of reptiles and amphibians at the San Diego Natural ...

(herpetologist) *

Hedy Lamarr Hedy Lamarr (; born Hedwig Eva Maria Kiesler; November 9, 1914 January 19, 2000) was an Austrian-born American film actress and inventor. A film star during Hollywood's golden age, Lamarr has been described as one of the greatest movie actresse ...

(actress) *

Harry Lindgren Harry Lindgren (25 June 1912 – 1 July 1992) was a British-Australian engineer, linguist and amateur mathematician. Early life Lindgren was born in Newcastle-upon-Tyne in England. In 1935 he emigrated to join his family in Perth, Australi ...

(civil servant) *

Ada Lovelace Augusta Ada King, Countess of Lovelace (''née'' Byron; 10 December 1815 – 27 November 1852) was an English mathematician and writer, chiefly known for her work on Charles Babbage's proposed mechanical general-purpose computer, the A ...

(countess) * Lu Jiaxi (high school physics teacher) *

Kenneth McIntyre Kenneth Gordon McIntyre OBE, ComIH (22 August 191020 May 2004) was an Australian lawyer and historian. Career McIntyre was born in Geelong in 1910 and graduated from Geelong College as Dux of the School in 1926. He went on to study Arts an ...

(lawyer) *

Danica McKellar Danica Mae McKellar (born January 3, 1975) is an American actress, mathematics writer, and education advocate. She played Winnie Cooper in the television series ''The Wonder Years'' from 1988 to 1993, and since 2010 has voiced Miss Martian in th ...

(actress) *

Anderson Gray McKendrick Lt Col Anderson Gray McKendrick DSc FRSE (8 September 1876 – 30 May 1943) was a Scottish military physician and epidemiologist who pioneered the use of mathematical methods in epidemiology. Irwin (see below) commented on the quality of his wor ...

(medical doctor) *

Marin Mersenne Marin Mersenne, OM (also known as Marinus Mersennus or ''le Père'' Mersenne; ; 8 September 1588 – 1 September 1648) was a French polymath whose works touched a wide variety of fields. He is perhaps best known today among mathematicians for ...

(theologian) *

Florence Nightingale Florence Nightingale (; 12 May 1820 – 13 August 1910) was an English Reform movement, social reformer, statistician and the founder of modern nursing. Nightingale came to prominence while serving as a manager and trainer of nurses during t ...

(nurse and statistician) *

George Phillips Odom Jr. George Phillips Odom Jr. (1941 – 18 December 2010) was an American artist and amateur geometer who is primarily known for his work on the golden ratio (\Phi). Life and work Odom garnered some recognition early in his career for his light machine ...

(artist) * B. Nicolò I. Paganini (schoolboy) *

Pāṇini , era = ;;6th–5th century BCE , region = Indian philosophy , main_interests = Grammar, linguistics , notable_works = ' (Sanskrit#Classical Sanskrit, Classical Sanskrit) , influenced= , notable_ideas=Descript ...

(linguist) *

Blaise Pascal Blaise Pascal ( , , ; ; 19 June 1623 – 19 August 1662) was a French mathematician, physicist, inventor, philosopher, and Catholic Church, Catholic writer. He was a child prodigy who was educated by his father, a tax collector in Rouen. Pa ...

(heir, private scholar) * Padmakumar (technician) *

Henry Perigal Henry Perigal, Jr. Royal Astronomical Society, FRAS Royal Institution, MRI (1 April 1801 – 6 June 1898) was a British stockbroker and amateur mathematician, known for his dissection problem, dissection-based proof of the Pythagorean theorem an ...

(stockbroker) *

Kenneth Perko In the mathematical theory of knots, the Perko pair, named after Kenneth Perko, is a pair of entries in classical knot tables that actually represent the same knot. In Dale Rolfsen's knot table, this supposed pair of distinct knots is labeled 1 ...

(lawyer) *

Ivan Pervushin Ivan Mikheevich Pervushin (russian: Иван Михеевич Первушин, sometimes transliterated as Pervusin or Pervouchine) (—) was a Russian clergyman and mathematician of the second half of the 19th century, known for his achievements ...

(priest) *

Piero della Francesca Piero della Francesca (, also , ; – 12 October 1492), originally named Piero di Benedetto, was an Italian painter of the Early Renaissance. To contemporaries he was also known as a mathematician and geometer. Nowadays Piero della Francesca i ...

(painter) *

Pingala Acharya Pingala ('; c. 3rd2nd century BCE) was an ancient Indian poet and mathematician, and the author of the ' (also called the ''Pingala-sutras''), the earliest known treatise on Sanskrit prosody. The ' is a work of eight chapters in the late ...

(musician) *

William Playfair William Playfair (22 September 1759 – 11 February 1823), a Scottish engineer and political economist, served as a secret agent on behalf of Great Britain during its war with France. The founder of graphical methods of statistics, Playfai ...

(draftsman) *

Henry Cabourn Pocklington Henry Cabourn Pocklington FRS (28 January 1870, Exeter – 15 May 1952, Leeds) was an English physicist and mathematician. His primary profession was as a schoolmaster, but he made important contributions to number theory Number theory (or ...

(schoolmaster) *

François Proth François Proth (22 March 1852 – 21 January 1879) was a French self-taught mathematician farmer who lived in Vaux-devant-Damloup near Verdun, France. He stated four primality-related theorems. The most famous of these, Proth's theorem, can ...

(farmer) * Ramchundra (head master) *

Marjorie Rice Marjorie Ruth Rice (née Jeuck) (1923–2017) was an American amateur mathematician most famous for her discoveries of pentagonal tilings in geometry. Background Rice was born February 16, 1923, in St. Petersburg, Florida. Marjorie Rice was a ...

(homemaker) *

Olinde Rodrigues Benjamin Olinde Rodrigues (6 October 1795 – 17 December 1851), more commonly known as Olinde Rodrigues, was a French banker, mathematician, and social reformer. In mathematics Rodrigues is remembered for Rodrigues' rotation formula for vectors, ...

(banker, social reformer) *

Lee Sallows Lee Cecil Fletcher Sallows (born April 30, 1944) is a British electronics engineer known for his contributions to recreational mathematics. He is particularly noted as the inventor of golygons, self-enumerating sentences, and geomagic squares. ...

(engineer) *

Robert Schlaifer Robert Osher Schlaifer (13 September 1914 – 24 July 1994) was a pioneer of Bayesian decision theory. At the time of his death he was William Ziegler Professor of Business Administration Emeritus of the Harvard Business School. In 1961 he was ...

(classics scholar) *

Robert Schneider Robert Peter Schneider (born March 9, 1971) is an American musician and mathematician. He is the lead singer, songwriter, guitarist and producer of rock/pop band the Apples in Stereo and has produced and performed on albums by Neutral Milk Ho ...

(musician and record producer) *

William Shanks William Shanks (25 January 1812 – June 1882) was an English amateur mathematician. He is famous for his calculation of '' '' (pi) to 707 places in 1873, which was correct up to the first 527 places. The error was discovered in 1944 by D. F. Fe ...

(landlord) * Abraham Sharp (schoolmaster) *

Simon Stevin Simon Stevin (; 1548–1620), sometimes called Stevinus, was a Flemish mathematician, scientist and music theorist. He made various contributions in many areas of science and engineering, both theoretical and practical. He also translated vario ...

(merchants clerk) *

Alicia Boole Stott Alicia Boole Stott (8 June 1860 – 17 December 1940) was an Irish mathematician. Despite never holding an academic position, she made a number of valuable contributions to the field, receiving an honorary doctorate from the University of Groni ...

(secretary) *

Paul Tannery Paul Tannery (20 December 1843 – 27 November 1904) was a French mathematician and historian of mathematics. He was the older brother of mathematician Jules Tannery, to whose ''Notions Mathématiques'' he contributed an historical chapter. Thoug ...

(tobacco factory director) *

Gaston Tarry Gaston Tarry (27 September 1843 – 21 June 1913) was a French mathematician. Born in Villefranche de Rouergue, Aveyron, he studied mathematics at high school before joining the civil service in Algeria. He pursued mathematics as an amateur. In ...

(civil servant) *

Niccolò Fontana Tartaglia Niccolò Fontana Tartaglia (; 1499/1500 – 13 December 1557) was an Italian mathematician, engineer (designing fortifications), a surveyor (of topography, seeking the best means of defense or offense) and a bookkeeper from the then Republi ...

(bookkeeper) *

Nikola Tesla Nikola Tesla ( ; ,"Tesla"
''

Sébastien Truchet Jean Truchet (1657 – 5 February 1729), known as Father Sébastian, was a French Dominican priest born in Lyon, who lived under the reign of Louis XIV. He was active in areas such as mathematics, hydraulics, graphics, typography, and for ...

(monk) *

Franciscus Vieta Franciscus is a Latin given name, originally an epithet meaning "the Frank, the Frenchman". It was applied to Saint Francis of Assisi (1181/82–1226). Francis had been baptized Giovanni (John); his father was Italian and his mother Proven� ...

(lawyer) *

Giordano Vitale Giordano Vitale or Vitale Giordano (October 15, 1633 – November 3, 1711) was an Italian mathematician. He is best known for his theorem on Saccheri quadrilaterals. He may also be referred to as Vitale Giordani, Vitale Giordano da Bitonto, an ...

(soldier) *

Walter Frank Raphael Weldon Walter Frank Raphael Weldon FRS (15 March 1860 – 13 April 1906), was an English evolutionary biologist and a founder of biometry. He was the joint founding editor of ''Biometrika'', with Francis Galton and Karl Pearson. Family Weldon was th ...

(evolutionary biologist) *

Johannes Werner Johann(es) Werner ( la, Ioannes Vernerus; February 14, 1468 – May 1522) was a German mathematician. He was born in Nuremberg, Germany, where he became a parish priest. His primary work was in astronomy, mathematics, and geography, although he ...

(parish priest) *

Caspar Wessel Caspar Wessel (8 June 1745, Vestby – 25 March 1818, Copenhagen) was a Danish–Norwegian mathematician and cartographer. In 1799, Wessel was the first person to describe the geometrical interpretation of complex numbers as points in the complex ...

(lawyer) *

Leo Wiener Leo Wiener (1862–1939) was an American historian, linguist, author and translator. Biography Wiener was born in Białystok (then in the Russian Empire), of Lithuanian Jewish origin. His father was Zalmen (Solomon) Wiener, and his mother was ...

(linguist) *

Frank Wilcoxon Frank Wilcoxon (2 September 1892 – 18 November 1965) was a chemist and statistician, known for the development of several statistical tests. Education and career Frank Wilcoxon was born to American parents on 2 September 1892 in County Cor ...

(chemist) *

Edouard Zeckendorf Edouard Zeckendorf (2 May 1901 – 16 May 1983) was a Belgian doctor, army officer and amateur mathematician. In mathematics, he is best known for his work on Fibonacci numbers and in particular for proving Zeckendorf's theorem, though he pu ...

(medical doctor)

References

{{reflist

Amateur mathematicians An amateur () is generally considered a person who pursues an avocation independent from their source of income. Amateurs and their pursuits are also described as popular, informal, self-taught, user-generated, DIY, and hobbyist. History Hi ...