Questions tagged [cipher]
A cipher is a simple method of modifying messages to make them unreadable except to readers who know the key. Common ciphers are Caesar, Vigenere, Atbash, and several types of substitution cipher. Other ciphers include polygraphic ciphers such as Playfair and Foursquare and numerical ciphers such as Polybius and Nihilist. Cipher puzzles sometimes make use of data encodings like Morse, Binary, or Base64.