The Enigma machine was the name that Germany gave the device it used to send encrypted coded messages in World War II. The Enigma machines were actually a series of electro-mechanical rotor cipher machines developed and used in the early to mid twentieth century to protect commercial, diplomatic and military messages/ 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. In fact, several different Enigma models were produced, but the German military Enigma models have been the most commonly recognized.

And, though Enigma had some cryptographic weaknesses, it was in fact German procedural flaws, operator mistakes, failure to systematically introduce changes in encipherment procedures, and Allied capture of key tables and hardware that, during the war, enabled Allied cryptologists to succeed in breaking Germany's Enigma.

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