In cryptography, a Caesar cipher, also known as Caesar's cipher, the shift cipher, Caesar's code or Caesar shift, is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet.
The Caesar shift cipher is actually 26 different ciphers, one for each letter of the alphabet. ROT1 is just one of these ciphers. A person only needs to be told which Caesar cipher was used in order to decipher a message. This cipher is the basis for many more complex ciphers, but on its own does not allow great protection of a secret message, as checking 26 different cipher keys does not take a relatively great amount of time. Li bra ghflskhu wklv dqg bra nqrz lw, fods brxu kdqgv.