The Enigma machine was a series of electro-mechanical rotor cipher machines created in 1918 and used commercially and by the military. Polish, French, and English scientists worked to decrypt Enigma messages in the early 1920s, with three Polish students solving the mystery of how Enigma encoded messages in 1932. As the Germans learned their messages were not secure, they improved the machine and encryption methods, requiring the Allies to continue working to decrypt messages during World War II from centers like Bletchley Park. Thanks to the efforts of Polish, English, and French scientists, the Allies were ultimately able to read messages encrypted by Enigma by the end of the war.