Alan Turing, British mathematician (1912-1954), altered the course of the 20th C. His 1936 paper laid the foundation of computer science, providing the first formal concept of a computer algorithm. In WWII he designed the machines that cracked German military codes. In the late 1940's he turned his attention to artificial intelligence and proposed a challenge, now called the Turing test, still important today. His contribution to mathematical biology was no less profound.
Joan Clarke, the cryptanalyst war-heroine, and the women of Bletchley Park (you never heard of)
Joan Clarke Murray codebreaker at Bletchley Park during World War II, became deputy head of Hut 8 in 1944. Code breaking was almost exclusively done by men during the war. Clarke was paid less than the men and felt that she was prevented from progressing further because of her gender. She was a English cryptanalyst and numismatist ~
Alan Turing, everyone (Had to learn about him from a movie!)
Alan Turing (1912 – 1954) - Turing is considered to be the father of theoretical computer science and artificial intelligence. During the Second World War, he worked at Bletchley Park, Britain's codebreaking centre. His work shortened the war in Europe by more than two years. Here seen in 1951.