Which type of cipher is the Caesar Cipher based on?

The Caesar Cipher is based on the ROT-3 substitution cipher. This method involves shifting each letter of the plaintext by a fixed number of places down or up the alphabet. In the case of the Caesar Cipher, this shift is specifically three positions, hence the term "ROT-3," which stands for "rotate by 3."

This is a straightforward substitution cipher, where each letter in the message is replaced with another letter a fixed number of places away in the alphabet. For example, an 'A' would shift to 'D', a 'B' to 'E', and so on, wrapping around to the beginning of the alphabet as necessary.

This foundational concept of shifting letters serves well to introduce the larger family of substitution ciphers, further distinguishing it from other types of encryption methods, such as symmetric and asymmetric key encryption, which rely on keys for encryption and decryption processes.