Which of the following is a substitution cipher used by ancient Hebrew scholars?

The Atbash cipher is a well-known substitution cipher that was used by ancient Hebrew scholars. In this cipher, the letters of the Hebrew alphabet are reversed. For instance, the first letter of the alphabet is substituted with the last letter, the second letter with the second-to-last letter, and so on. This method is simple but effective, allowing for the encoding of messages in a way that could easily be decrypted by someone who understood the system.

The Atbash cipher has a rich historical significance, particularly among Jewish scholars, as it was referenced in various biblical texts. Its simplicity and directness made it an accessible method of encoding messages without requiring complex algorithms or extensive keys.

In contrast, other ciphers like the Caesar cipher involve a fixed shift of letters, the Vigenère cipher uses a keyword to determine shifts, and the Playfair cipher encodes pairs of letters, making them more complex than the Atbash. Each of these has distinct features and applications that set them apart from the straightforward approach of the Atbash cipher used by ancient Hebrew scholars.