Inspired by the Information security subject and as part of my study, I started playing with some of the encryption method and decided to share them with others. The tests may become handy in some of my future projects so it's better to keep them safe here.
Ref: http://practicalcryptography.com/ciphers/homophonic-substitution-cipher/
Ref: https://www.youtube.com/watch?v=4zahvcJ9glg
Ref: http://practicalcryptography.com/ciphers/simple-substitution-cipher/
Ref: https://en.wikipedia.org/wiki/Vigen%C3%A8re_cipher
Ref: https://www.tutorialspoint.com/cryptography/feistel_block_cipher.htm