Answer:
During World War II, the Allied forces used a variety of methods to break enemy codes, including intercepting and decrypting enemy messages, and developing sophisticated code-breaking machines such as the British Bombe and the American SIGABA. They also employed a large number of codebreakers who worked to decipher messages by hand, and used intelligence obtained through espionage and other means to help them break codes. One of the most famous code-breaking efforts during the war was the Allied effort to break the German Enigma code, which was accomplished through a combination of mathematical analysis, technological innovation, and intelligence gathering.