Текст:

- Caesar cipher https://en.wikipedia.org/wiki/Caesar_cipher

- Polyalphabetic cipher https://en.wikipedia.org/wiki/Polyalphabetic_cipher

- Enigma machine https://en.wikipedia.org/wiki/Enigma_machine

- Хватит искать всему практическое применение https://rakh.im/practical/

Видео:

- Enigma (video by Numberphile) https://youtu.be/G2_Q9FoD-oQ

- Gambling with Secrets https://www.youtube.com/playlist?list=PLB4D701646DAF0817

- Cryptography Course (Khan Academy) https://www.youtube.com/playlist?list=PL148EBF39F493C3DE

- Алгоритм Диффи-Хеллмана https://rakh.im/diffie_hellman/