Alan Turing was a complicated and eccentric genius – a man ahead of his time. In the 1930s, this British mathematician envisioned a digital world few others could imagine. During World War II, he broke the German naval Enigma code and helped Britain defeat the Nazis. As the father of computer science and a leading theorist of artificial intelligence, today Turing is considered one of the 20th century’s most important people. He never saw the world he helped create: instead, after being persecuted for his homosexuality by the government he helped save, Turing took his own life in 1954.