"Floradora", also called Keyword, was a doubly enciphered diplomatic code used by the Germans during the Second World War. The Allies used tabulating equipment, created by IBM, to break the code over period of more than a year in 1941 and 1942.

References

• Budiansky, Stephen. Battle of wits: the complete story of codebreaking in World War II, p. 55. Simon and Schuster, 2000
• Cowan, Michael (5 August 2012). "How the Allies broke the German Diplomatic cipher Floradora" (PDF). Retrieved 2 August 2023.