Cryptanalysis of the Enigma by the letters on the top row of the Enigma keyboard. So, "continuation of message sent at 2330" was represented as "FORTYWEEPYYWEEPY". "Cribs" were fundamental to the British approach to solving Enigma keys, but guessing the plaintext for a message was a highly skilled business. So in 1940 Stuart Milner-Barry set up a special "Crib Room" in Hut 8. Foremost amongst the knowledge needed for identifying cribs was the text of previous decrypts. Bletchley Park maintained detailed indexes of message preambles, of every person, of every ship, of every unit, of every weapon, of every technical term and of repeated
Enigma machine countries used Enigma machines. The Italian Navy adopted the commercial Enigma as "Navy Cipher D". The Spanish also used commercial Enigma during their Civil War. British codebreakers succeeded in breaking these machines, which lacked a plugboard. Enigma were also used by diplomatic services. There was also a large, eight-rotor printing model, the "Enigma H", called "Enigma II" by the "Reichswehr". In 1933 the Polish Cipher Bureau detected that it was in use for high-level military communications, but that it was soon withdrawn, as it was unreliable and jammed frequently. The Swiss used a version of Enigma called "model K" or