During the Second World War, 
the British Secret Service called on Turing to solve 
a problem of international significance. To encode 
all of their strategic messages, the Germans had 
created a machine, Enigma, that was said to 
produce unbreakable codes. 

Alan Turing designed another electromechanical machine, the “bomb”, that allowed the British to decipher enemy communications. Turing is known 
to have outlined the concept of a stored program distinct from the machine itself. However, some of his war work is still classified as a military secret and remains shrouded in mystery.