Sir Charles Antony Richard Hoare FRS FREng (born 11 January 1934)  is a British  computer scientist. He developed the sorting algorithm quicksort in 1959–1960. He also developed  Hoare logic for verifying program correctness, and the formal language communicating sequential processes (CSP) to specify the interactions of concurrent processes (including the dining philosophers problem) and the inspiration for the programming language occam.     
Education and early life
Colombo, Ceylon (now Sri Lanka) to British parents, Tony Hoare's father was a colonial civil servant and his mother was the daughter of a tea planter. Hoare was educated in England at the Dragon School in Oxford and the King's School in Canterbury. He then studied  Classics and Philosophy ("Greats") at Merton College, Oxford. On graduating in 1956 he did 18 months  National Service in the Royal Navy, where he learned Russian.  He returned to the  University of Oxford in 1958 to study for a postgraduate certificate in statistics, and it was here that he began  computer programming, 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 under Andrey Kolmogorov.
Research and career
In 1960, Hoare left the
Soviet Union 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 algorithms. 
He served as a member of the
International Federation for Information Processing (IFIP) IFIP Working Group 2.1, which supports and maintains the languages ALGOL 60 and ALGOL 68.
He became the Professor of
Computing Science 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), following the death of Christopher Strachey. He is now an Emeritus Professor there, and is also a principal researcher at Microsoft Research in Cambridge, 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 processes, structuring computer operating systems using the monitor concept, and the axiomatic specification of programming languages. 
Apologies and retractions
Speaking at a software conference named QCon London
in 2009, he apologised for inventing the  null reference:
I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (
ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.
For many years under his leadership, his 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:
Ten years ago, researchers into formal methods (and I was the most mistaken among them) predicted that the programming world would embrace with gratitude every assistance promised by formalisation to solve the problems of reliability that arise when programs get large and more safety-critical. Programs have now got very large and very critical – well beyond the scale which can be comfortably tackled by formal methods. There have been many problems and failures, but these have nearly always been attributable to inadequate analysis of requirements or inadequate management control. It has turned out that the world just does not suffer significantly from the kind of problem that our research was originally intended to solve.
In 1962, Hoare married Jill Pym, a member of his research team.
Awards and honours
Distinguished Fellow of the British Computer Society (1978)
ACM Turing Award 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, 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 
Harry H. Goode Memorial Award (1981)
Fellow of the Royal Society (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 (2000)
Kyoto Prize for Information science (2000)
Fellow of the  Royal Academy of Engineering (2005) 
Computer History Museum (CHM) in Mountain View, California 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 (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 (2013) 
^ a b
Tony Hoare at the Mathematics Genealogy Project
Sampaio, Augusto (1993). . An algebraic approach to compiler design bodleian.ox.ac.uk (DPhil thesis). University of Oxford. OCLC 854973008. EThOS uk.bl.ethos.334903.
^ a b c
"List of Fellows".
"Birthdays Jan 10". . London. 10 January 2009 The Times . Retrieved . 9 January 2010
"Sir Antony Hoare". Computer History Museum. Archived from the original on 3 April 2015 . Retrieved . 22 April 2015
Tony Hoare author profile page at the ACM Digital Library
C. A. R. Hoare at DBLP Bibliography Server
List of publications from Microsoft Academic
Shustek, L. (2009). "Interview: An interview with C.A.R. Hoare". . Communications of the ACM 52 (3): 38–41. doi: 10.1145/1467247.1467261.
Hoare, C. A. R. (1974). "Monitors: An operating system structuring concept". Communications of the ACM. 17 (10): 549–557. doi: 10.1145/355620.361161.
Bowen, Jonathan (8 September 2006). Oral History of Sir Antony Hoare (PDF). Hoare (Sir Antony, C.A.R.) Oral History, CHM Reference number: X3698.2007 (Report). Computer History Museum. Archived from the original on 2013 . Retrieved . 18 April 2014
Lean, Thomas (2011). "Professor Sir Tony Hoare" (PDF). National Life Stories: An Oral History of British Science. UK: British Library . Retrieved . 15 September 2014
^ a b c d e
Levens, R.G.C., ed. (1964). Merton College Register 1900-1964. Oxford: Basil Blackwell. p. 434.
^ a b
Hoare, Tony (Autumn 2009). "My Early Days at Elliotts". Resurrection (48). ISSN 0958-7403 . Retrieved . 27 May 2014
Roscoe, Bill; Jones, Cliff (2010). "1 Insight, inspiration and collaboration" (PDF). Reflections on the Work of C.A.R. Hoare. Springer. ISBN . 978-1-84882-911-4
^ a b
Hoare, C.A.R. (February 1981). "The emperor's old clothes". . Communications of the ACM 24 (2): 5–83. doi: 10.1145/358549.358561. ISSN 0001-0782.
Hoare, C. A. R. (1981). "The emperor's old clothes". Communications of the ACM. 24 (2): 75–83. doi: 10.1145/358549.358561.
Jeuring, Johan; Meertens, Lambert; Guttmann, Walter (17 August 2016). "Profile of IFIP Working Group 2.1". Foswiki . Retrieved . 8 March 2020
Microsoft home page – short biography
Oral history interview with C. A. R. Hoare at Charles Babbage Institute, University of Minnesota, Minneapolis.
The classic article on monitors – The original article on monitors
"Preface to the ACM Turing Award lecture" (PDF). Archived from the original (PDF) on 19 April 2012.
"C. Antony (Tony) R. Hoare". Archived from the original on 1 July 2012.
Hoare, Tony (25 August 2009). "Null References: The Billion Dollar Mistake". InfoQ.com.
Hoare, C. A. R. (1996). "Unification of Theories: A Challenge for Computing Science". Selected papers from the 11th Workshop on Specification of Abstract Data Types Joint with the 8th COMPASS Workshop on Recent Trends in Data Type Specification. Springer-Verlag. pp. 49–57. ISBN . 3-540-61629-2
Jones, Cliff; Roscoe, A. W.; Wood, Kenneth R., eds. (2010). Reflections on the Work of C.A.R. Hoare. Springer Science. p. 3. Bibcode: 2010rwch.book.....R.
Hoare, Charles Anthony Richard (27 October 1980). "The Emperor's Old Clothes: The 1980 ACM Turing Award Lecture" (PDF). Association for Computing Machinery. Archived from the original (PDF) on 19 April 2012.
Anon (1982). "Anthony Hoare FRS". royalsociety.org. London: Royal Society.
"Honorary Graduates 1989 to present". bath.ac.uk. University of Bath . Retrieved . 18 February 2012
(Charles) Antony Richard (Tony) Hoare Biography
"Sir Antony Hoare: 2006 Fellow". Archived from the original on 3 April 2015 . Retrieved . 8 March 2020 "Archived copy". Archived from the original on 3 April 2015 . Retrieved . 22 April 2015 CS1 maint: archived copy as title ( link)
"Annual Review 2007: Principal's Review". www1.hw.ac.uk. Archived from the original on 5 March 2016 . Retrieved . 29 March 2016
"Preisverleihung auf der Festveranstaltung "40 Jahre Informatik in München": TU München vergibt Friedrich L. Bauer-Preis an Tony Hoare" (in German). Technical University of Munich. 26 October 2007. Archived from the original on 10 June 2016 . Retrieved . 14 May 2016
"Programming Languages Achievement Award 2011". ACM . Retrieved . 28 August 2012
"IEEE John von Neumann Medal Recipients" (PDF). IEEE . Retrieved . 26 February 2011
Krzysztof, Diks (15 November 2012). "Profesor Hoare doktorem honoris causa Uniwersytetu Warszawskiego" (in Polish). University of Warsaw. Archived from the original on 26 August 2014 . Retrieved . 26 November 2012
"Los informáticos Tony Hoare y Mateo Valero serán investidos hoy doctores honoris causa por la Complutense" (in Spanish). 10 May 2013 . Retrieved . 10 May 2013
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