So many technologies of Code Encrption were used and could have been used in WW2 by both sides. David Kahn in his book THE CODEBREAKERS stated why did not the Germans, some of whom relaized that their Enigma Code Machine was far from infallible, did not adopt new dissimilar machines. Well his(Kahn's) answer was:"they did they not have another machine" That is far from true. The above are alternatives to Enigma: The Hitler-Muhle(Mill). Mill is German slang for 'typewriter'.