Alan Turing, English mathematician and computer scientist (died 1954)

Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. He was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science.

June 23 is the 174th day of the year in the Gregorian calendar; 191 days remain until the end of the year.