Caesar cipher is an algorithm that creates ciphertext.
It moves each letter of the plaintext forwards or backwards in the alphabet by N.
If you are at A or Z, it wraps back around.
So if the message is ‘izak’ and we’re moving it forward by 3 what would it be?
It’d be lcdn.
I - j, k, L
Z - a, b, C
A - b, c, D
K - l, m, N
This is a simple Substitution Cipher
Additional information, it was named after a roman soldier Julius Caesar from 100-44 BC and used it during the Gallic Wars to communicate with allies and hide communications from the enemy.