WW2 Enigma Cipher Machine

The German military used the Enigma cipher machine during WW2 to keep their communications secret. The army, navy and air force all encoded their messages using Enigma, believing that the machine would make these communications impenetrable to the enemy.

The Enigma machine is an electro-mechanical device that relies on a series of rotating 'wheels' to scramble plaintext messages into incoherent ciphertext. The machine's variable elements can be set in many billions of combinations, and each one will generate a completely different ciphertext message. If you know how the machine has been set up, you can type the ciphertext back in and it will unscramble the message. If you don't know the Enigma setting, the message remains indecipherable.

The German authorities believed in the absolute security of the Enigma, but British code breakers stationed at Bletchley Park during WW2 managed to exploit weaknesses in the machine and how it was used and were able to crack the Enigma code.

During the war there were thousands of machines, as every German military unit needed one to encipher and decipher coded messages. But sixty years on, very few remain. The Enigma I use in my demonstrations is a genuine machine, built in 1936 and used by the army in France during the war. It's still in perfect working order and maintains virtually all of its original parts.