References
Videos for further learning
The One-Time Pad
The Enigma Machine
How was Enigma Machine cracked?
Claude Shannon: A Mathematical Theory of Communication
The One Time Pad System
The Enigma Machine
Enigma Machine Simulator
https://www.theguardian.com/technology/2014/nov/14/how-did-enigma-machine-work-imitation-game
German Military Tactics
https://en.wikipedia.org/wiki/High-frequency_direction_finding