As a 20th-century mathematician, Alan Turing left an indelible mark on the field of computer science. In his 20s, he proposed the "Turing Machine," a thought experiment about how a universal multitask computer could work, a concept which forms the basis for every computer built today. During World War II, Turing worked as a code breaker for Britain, and helped break the Enigma code used by the Nazi war machine, creating a tactical advantage for the Allies. Following the war, Turing developed an interest in artificial intelligence, proposing the "Turing Test": If a computer could fool a human into thinking it was also human, the computer would "pass" the test—something no computer has done yet. Alan Turing: Computing Genius and Wartime Codebreaker offers a voyage through the mathematician's mind and thought processes and invites readers to explore mathematics, computing, artificial intelligence, and codebreaking. Researchers will find sidebars that highlight points of interest and relevant ideas, a timeline that draws attention to key points in Turing's career, and a glossary that clarifies difficult terms.