Introduction to ciphers and substitution. Alice and Bob and Carl and Julius: terminology and Caesar Cipher ; The key to the matter: generalizing the Caesar Cipher ; Multiplicative ciphers ; Affine ...

Introduction If you need to send a secret message to a friend, how could you prevent other people from reading it? One way is to encrypt the message—that is, use a secret code that only you and your ...

Cryptography puts the “crypto” in cryptocurrency. It has existed much longer than our digital age and has evolved like languages over the centuries. One of the most famous uses was developed by Julius ...