Editor's Note: Born on June 23, 1912, Alan Turing was a British scientist and a pioneer in computer science. During World War II, he developed a machine that helped break the German Enigma code. He also laid the groundwork for modern computing and theorized about artificial intelligence. In 1936 he created the "Turing machine" that could compute anything that was computable. In honor of his birthday, we present this timeline of computer history.