Tony Hoare

Tony Hoare is a British computer scientist who made foundational contributions across several core areas of computer science, beginning in 1959 and 1960 when, while working on a machine translation project in Moscow, he devised the quicksort algorithm, a highly efficient method for sorting lists of data that works by repeatedly partitioning a list around a chosen reference value, an algorithm that remains one of the most widely taught and widely used sorting methods in computing today. Hoare later developed a formal mathematical system, now called Hoare logic, that provides a precise, rigorous way to reason about and prove that a computer program will actually behave correctly according to its specification, a foundational tool for the later field of formal software verification. He also introduced communicating sequential processes, usually abbreviated CSP, a formal mathematical language for describing and reasoning about systems made up of multiple independent processes that interact only by explicitly passing messages to one another, an approach that became influential in the design of concurrent and parallel computing systems, and together with fellow computer scientist Edsger Dijkstra he formulated the well known dining philosophers problem, a scenario used to illustrate the practical difficulties of managing shared resources safely among multiple concurrent processes. Hoare was awarded the 1980 Turing Award, computer science's highest honor, for his fundamental contributions to the definition and design of programming languages, and he spent much of his academic career at the University of Oxford and later as a researcher at Microsoft Research Cambridge.