The wife and I have been watching "The Bletchley Circle" on PBS. The characters in the program are based on 4 women who were code breakers in England during WWII. The technology of the time sparked my interest so I decided to look into it a little further. If you are interested there is a fairly detailed Wiki here:
https://en.wikipedia.org/wiki/Bletchley_ParkHere are a couple of photos of the decipher machines they used. Just think, the computer power they used at the time was much less powerful then your cell/mobile phone. But they had tubes so they were cool err... well... maybe not so cool.
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.apprendre-en-ligne.net%2Fcrypto%2FEnigma%2Fbombe.jpg&hash=6cdf3230df1c06edd094d1f60581a3754acebd6a)
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fwww.descubridores.com%2Fwp-content%2Fuploads%2F2013%2F06%2FColossus_Mark2_Bletchley_Park-736x600.jpg&hash=eaac6be05bbce1848d9c2483ce4f2ce65e08ad17)
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm4.staticflickr.com%2F3077%2F3240102420_2a41441bd5_z.jpg&hash=fbabc915d058c7aa405a538dd68323639cc9a11e)
(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Ffarm3.staticflickr.com%2F2653%2F3894648406_1524ac85ba_z.jpg&hash=253399e1dc8d7b599fc9ebf5b863353b06fa5055)