Alan Turing was a British computer scientist, mathematician, logician, cryptanalyst, philosopher, and theoretical biologist. He is widely considered to be the father of computer science and artificial intelligence. Turing was highly influential in the development of theoretical computer science, providing a formalization of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. He also made major contributions to cryptanalysis, including his famous paper on breaking the Enigma code during World War II. Turing's work has had a lasting impact on the fields of computer science, mathematics, and philosophy.