Whose Mathematics Founded Computer Science?

In 1936, British mathematician Alan Turing (1912-1954) published one of the most influential papers in history, introducing the concept of a "universal computing machine" — now called a Turing machine. This abstract device could simulate any algorithm by reading and writing symbols on an infinite tape according to a set of rules. Turing proved that such a machine could compute anything that is computable, and crucially, that some problems (like the "halting problem") are fundamentally undecidable. During World War II, Turing led the effort at Bletchley Park to break German Enigma codes, building the electromechanical "bombe" that decoded thousands of messages daily — work credited with shortening the war by an estimated 2 years and saving millions of lives. After the war, he worked on early computer designs (ACE at the National Physical Laboratory), proposed the "Turing test" for machine intelligence (1950), and studied morphogenesis in biology. Prosecuted for homosexuality in 1952, he died in 1954; he received a posthumous royal pardon in 2013.