Caesar cipher
The Caesar cipher, named after Julius Caesar who is believed to have used it for secure communication, is a simple and very old encryption technique. It is a type of substitution cipher where each letter in the plaintext is shifted a certain number of places down or up the alphabet.
Hash Functions
Hash functions are algorithms that transform input data into a fixed-size string of characters, commonly referred to as a hash value or digest. These functions are essential in computer science and cryptography for purposes such as ensuring data integrity, securely storing passwords, and creating digital signatures.