The first mechanical encryption device was introduced in 1920 and named the rotor machine. The most famous example of a rotor machine is the Enigma, invented by the Germans; it was extensively used during World War II.
The concept of the rotor machine was developed independently by a number of inventors at a similar time. Four inventors had been credited with inventing it: Edward Hebern, Arvid Damm, Hugo Koch, and Arthur Scherbius. However, in later discovery, it was found that the first inventors ...