Sir Charles Antony Richard Hoare (Tony Hoare or C. A. R. Hoare) (born 11 January 1934) is a British computer scientist who has made foundational contributions to programming languages,

algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

s, formal verification, and concurrent computing. His work earned him the

Turing Award The ACM A. M. Turing Award is an annual prize given by the Association for Computing Machinery (ACM) for contributions of lasting and major technical importance to computer science. It is generally recognized as the highest distinction in compu ...

, usually regarded as the highest distinction in computer science, in 1980. Hoare developed the sorting algorithm quicksort in 1959–1960. He developed Hoare logic, an axiomatic basis for verifying program correctness. In the semantics of concurrency, he introduced the formal language communicating sequential processes (CSP) to specify the interactions of concurrent processes, and along with Edsger Dijkstra, formulated the dining philosophers problem. He is also credited with development (and later criticism) of the null pointer, having introduced it in the ALGOL family of languages. Since 1977, he has held positions at the

University of Oxford , mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor ...

and Microsoft Research in

Cambridge Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...

Education and early life

Tony Hoare was born in

Colombo Colombo ( ; si, කොළඹ, translit=Koḷam̆ba, ; ta, கொழும்பு, translit=Koḻumpu, ) is the executive and judicial capital and largest city of Sri Lanka by population. According to the Brookings Institution, Colombo me ...

, Ceylon (now

Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...

) to British parents; his father was a colonial civil servant and his mother was the daughter of a tea planter. Hoare was educated in

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

at the

Dragon School ("Reach for the Sun") , established = 1877 , closed = , type = Preparatory day and boarding school and Pre-Prep school , religion = Church of England , president = , head_label = Head , head = Emma Goldsm ...

Oxford Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the ...

and the King's School in

Canterbury Canterbury (, ) is a cathedral city and UNESCO World Heritage Site, situated in the heart of the City of Canterbury local government district of Kent, England. It lies on the River Stour. The Archbishop of Canterbury is the primate of t ...

. He then studied Classics and Philosophy ("Greats") at Merton College, Oxford. On graduating in 1956 he did 18 months

National Service National service is the system of voluntary government service, usually military service. Conscription is mandatory national service. The term ''national service'' comes from the United Kingdom's National Service (Armed Forces) Act 1939. The ...

in the

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against Fr ...

, where he learned Russian. He returned to the

University of Oxford , mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor ...

in 1958 to study for a postgraduate certificate in

statistics Statistics (from German: '' Statistik'', "description of a state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a scientific, indust ...

, and it was here that he began

computer programming Computer programming is the process of performing a particular computation (or more generally, accomplishing a specific computing result), usually by designing and building an executable computer program. Programming involves tasks such as anal ...

, having been taught Autocode on the Ferranti Mercury by Leslie Fox. He then went to Moscow State University as a British Council exchange student, where he studied

machine translation Machine translation, sometimes referred to by the abbreviation MT (not to be confused with computer-aided translation, machine-aided human translation or interactive translation), is a sub-field of computational linguistics that investigates ...

under

Andrey Kolmogorov Andrey Nikolaevich Kolmogorov ( rus, Андре́й Никола́евич Колмого́ров, p=ɐnˈdrʲej nʲɪkɐˈlajɪvʲɪtɕ kəlmɐˈɡorəf, a=Ru-Andrey Nikolaevich Kolmogorov.ogg, 25 April 1903 – 20 October 1987) was a Sovi ...

Research and career

In 1960, Hoare left the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

and began working at Elliott Brothers Ltd, a small computer manufacturing firm located in London. There, he implemented the language ALGOL 60 and began developing major

s. He was involved with developing international standards in programming and informatics, as a member of the International Federation for Information Processing (IFIP) Working Group 2.1 on Algorithmic Languages and Calculi, which specified, maintains, and supports the languages ALGOL 60 and ALGOL 68. He became the Professor of

Computing Science Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to practical disciplines (including ...

at the Queen's University of Belfast in 1968, and in 1977 returned to Oxford as the Professor of Computing to lead the Programming Research Group in the Oxford University Computing Laboratory (now

Department of Computer Science, University of Oxford The Department of Computer Science is the computer science department of the University of Oxford, England, which is part of the university's Mathematical, Physical and Life Sciences Division. It was founded in 1957 as the Computing Laboratory ...

), following the death of Christopher Strachey. He is now an Emeritus Professor there, and is also a principal researcher at Microsoft Research in

, England. Hoare's most significant work has been in the following areas: his sorting and selection algorithm ( Quicksort and Quickselect), Hoare logic, the formal language communicating sequential processes (CSP) used to specify the interactions between

concurrent process Concurrent computing is a form of computing in which several computations are executed '' concurrently''—during overlapping time periods—instead of ''sequentially—''with one completing before the next starts. This is a property of a syst ...

es (and implemented in various programming languages such as occam), structuring computer

s using the

monitor Monitor or monitor may refer to: Places * Monitor, Alberta * Monitor, Indiana, town in the United States * Monitor, Kentucky * Monitor, Oregon, unincorporated community in the United States * Monitor, Washington * Monitor, Logan County, West ...

concept, and the axiomatic specification of programming languages. Speaking at a software conference in 2009, Tony Hoare apologized for inventing the null reference: For many years under his leadership, Hoare's Oxford department worked on formal specification languages such as CSP and Z. These did not achieve the expected take-up by industry, and in 1995 Hoare was led to reflect upon the original assumptions:

Awards and honours

Distinguished Fellow of the British Computer Society Distinguished Fellow of the British Computer Society (DFBCS or DistFBCS) is an award and fellowship granted by the British Computer Society for members of the computing profession who have made an outstanding contribution to the advancement of co ...

(1978) *

for "fundamental contributions to the definition and design of programming languages". The award was presented to him at the ACM Annual Conference in

Nashville, Tennessee Nashville is the capital city of the U.S. state of Tennessee and the seat of Davidson County. With a population of 689,447 at the 2020 U.S. census, Nashville is the most populous city in the state, 21st most-populous city in the U.S., and ...

, on 27 October 1980, by Walter Carlson, chairman of the Awards committee. A transcript of Hoare's speech was published in ''

Communications of the ACM ''Communications of the ACM'' is the monthly journal of the Association for Computing Machinery (ACM). It was established in 1958, with Saul Rosen as its first managing editor. It is sent to all ACM members. Articles are intended for readers wi ...

''. *

Harry H. Goode Memorial Award The Harry H. Goode Memorial Award is an IEEE Computer Society annual awards in honor of Harry H. Goode for achievements in the information processing field which are considered either a single contribution of theory, design, or technique of outsta ...

(1981) *

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...

(1982) * Honorary Doctorate of Science by the Queen's University Belfast (1987) * Honorary Doctorate of Science, from the University of Bath (1993) * Honorary Fellow, Kellogg College, Oxford (1998) * Knighted for services to education and

computer science Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...

( 2000) * Kyoto Prize for

Information science Information science (also known as information studies) is an academic field which is primarily concerned with analysis, collection, classification, manipulation, storage, retrieval, movement, dissemination, and protection of information. ...

(2000) * Fellow of the Royal Academy of Engineering (2005) * Member of the National Academy of Engineering (2006) for fundamental contributions to computer science in the areas of algorithms, operating systems, and programming languages. * Computer History Museum (CHM) in

Mountain View, California Mountain View is a city in Santa Clara County, California, United States. Named for its views of the Santa Cruz Mountains, it has a population of 82,376. Mountain View was integral to the early history and growth of Silicon Valley, and is t ...

Fellow of the Museum "for development of the Quicksort algorithm and for lifelong contributions to the theory of programming languages" (2006) * Honorary Doctorate from Heriot-Watt University (2007) * Honorary Doctorate of Science from the Department of Informatics of the

Athens University of Economics and Business Athens University of Economics and Business (AUEB; el, Οικονομικό Πανεπιστήμιο Αθηνών, ''Oikonomiko Panepistimio Athinon'', abbrev. ΟΠΑ, OPA) was founded in 1920 in Athens, Greece and is the oldest university in G ...

(AUEB) (2007) * Friedrich L. Bauer-Prize, Technical University of Munich (2007) * SIGPLAN Programming Languages Achievement Award (2011) * IEEE John von Neumann Medal (2011) * Honorary Doctorate, University of Warsaw (2012) * Honorary Doctorate,

Complutense University of Madrid The Complutense University of Madrid ( es, Universidad Complutense de Madrid; UCM, links=no, ''Universidad de Madrid'', ''Universidad Central de Madrid''; la, Universitas Complutensis Matritensis, links=no) is a public research university loc ...

(2013) * 1973 ACM Programming Systems and Languages Paper Award, for the paper "Proof of correctness of data representations"

Personal life

In 1962, Hoare married Jill Pym, a member of his research team.

Books

* * C. A. R. Hoare (1985). '' Communicating Sequential Processes''. Prentice Hall International Series in Computer Science. (hardback) or (paperback). (Available online at http://www.usingcsp.com/ in PDF format.) * * *

References

External links

* {{DEFAULTSORT:Hoare, Tony 1934 births Living people People from Colombo People educated at The Dragon School People educated at The King's School, Canterbury Alumni of Merton College, Oxford Academics of Queen's University Belfast British computer scientists Fellows of the British Computer Society Fellows of the Royal Academy of Engineering Fellows of the Royal Society Foreign associates of the National Academy of Sciences Fellows of Wolfson College, Oxford Formal methods people History of computing in the United Kingdom Knights Bachelor Kyoto laureates in Advanced Technology Members of the Department of Computer Science, University of Oxford Microsoft employees Moscow State University alumni Programming language researchers Turing Award laureates Computer science writers British expatriates in Sri Lanka British expatriates in the Soviet Union Fellows of Merton College, Oxford