Enigma machine

The Enigma machines were a series of electro-mechanical rotor cipher machines developed and used in the early- to mid-20th century to protect commercial, diplomatic and military communication. Enigma was invented by the German engineer Arthur Scherbius at the end of World War I. Early models were used commercially from the early 1920s, and adopted by military and government services of several countries, most notably Nazi Germany before and during World War II. Several different Enigma models were produced, but the German military models are the most commonly recognised. However, Japanese and Italian models have been used.

On 26 and 27 July 1939, in Pyry near Warsaw, Polish intelligence initiated French and British military intelligence representatives into their Enigma-decryption techniques and equipment, including Zygalski sheets and the cryptologic bomb, and promised each delegation a Polish-reconstructed Enigma. The demonstration represented a vital basis for the later British continuation and effort. During the war, British cryptologists decrypted a vast number of messages enciphered on Enigma. The intelligence gleaned from this source, codenamed "Ultra" by the British, was a substantial aid to the Allied war effort.

Engima machine in "News From the Front"
On April 25, 1942, the New York Times reported on British and other Allied efforts to decode captured German Engima machines. No American administration official would speak on the record, or even admit on the record that code-breaking activities were taking place. The Times asked why better use had not been made of captured information, and opined that if the Allies were reading the enemies' codes, they had little to show for it.