Christopher Strachey

Christopher Strachey (1916–1975) was a British computer scientist, one of the founders of denotational semantics, and a pioneer in programming language design and computer time-sharing, also been credited as possibly being the first developer of a video game.

Strachey was born to a prominent English family. Stracheys belonged to the Bloomsbury Group whose members included Virginia Woolf, John Maynard Keynes, and Christopher’s uncle Lytton Strachey. At 13, Christopher went to Gresham’s School in Norfolk, where he showed signs of brilliance but in general, performed poorly. Then in 1935, he was admitted to King’s College, Cambridge (just as Alan Turing), where he studied mathematics and then transferred to physics, but continued to neglect his studies. At the end of his third year at Cambridge, Christopher suffered a nervous breakdown, possibly related to coming to terms with his homosexuality. He returned to Cambridge but managed only a “lower second” in the Natural Sciences Tripos.

In 1940, Strachey joined Standard Telephones and Cables (STC) as a research physicist, where he saw a calculating machine—a differential analyzer, which sparked his interest and he began to research the topic. After the war, he became a schoolmaster at St Edmund’s School, Canterbury, and three years later he was able to move to the more prestigious Harrow School in 1949, where he stayed for three years.

In early 1951, Strachey began his career as a programmer, using a reduced version of Turing’s Automatic Computing Engine (ACE) the concept of which dated from 1945: the Pilot ACE. In his spare time, Strachey developed a program for the game of draughts (also known as “checkers”), which he finished a preliminary version in May 1951. The game completely exhausted the Pilot ACE’s memory. The draughts program tried to run for the first time on 30 July 1951 but was unsuccessful due to program errors. When Strachey heard about the Manchester Mark 1, which had a much bigger memory, he asked his former fellow student Alan Turing for the manual and transcribed his program into the operation codes of that machine by October 1951. By the summer of 1952, the program could “play a complete game of Draughts at a reasonable speed”. It may have been the first video game.

In 1951 Strachey programmed the first computer music in England and the earliest recording of music played by a computer—a rendition of the British National Anthem “God Save the King” on the Ferranti Mark 1 computer. During the summer of 1952, Strachey programmed a love letter generator for the Ferranti Mark 1 which is known as the first example of computer-generated literature.

In 1959 Strachey developed the concept of time-sharing, and filed a patent application in February of that year, and gave a paper “Time Sharing in Large Fast Computers” at the inaugural UNESCO Information Processing Conference in Paris where he passed the concept on to Joseph Licklider.