Alan Turing was a pioneering mathematician and logician known for his critical contributions to the field of computing. Turing's work during World War II, particularly his role in breaking the Enigma code, demonstrated the practical applications of his mathematical theories. He also developed the concept of the Turing machine, which is foundational in computer science for understanding algorithms and computation. Turing's insights laid the groundwork for modern computers and artificial intelligence, and he is often referred to as the father of computer science.