The Enigma machine was an electromechanical encryption device invented in 1918 by German electrical engineer Arthur Scherbius. The Enigma machine was used by the German military to send encrypted messages up to the end of World War II. Using an electromechanical rotor mechanism, the Enigma machine scrambles the letters of the alphabet to ciphertext. This cipher machine in the form of a typewriter came in multiple variations for different purposes including banking and military.

Although thought to be unbreakable, in 1932, Polish cryptanalyst Marian Rejewski, first cracked the Enigma code. Like any machine, what's most important is how securely it is used. During World War 2, mathmetician and cryptanalyst Alan Turing, along with 10,000 over servicemen and women from the Government Code and Cypher School, continued work on breaking the Enigma code. The decryption of the Eniga code is considered one of the most valuable sources of intelligence for the Allies during WWII.

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