Carroll published "The Alphabet-Cipher" in 1868, possibly in a children's magazine. It describes what is known as a Vigenère cipher, a well-known scheme...

of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with...

by writing out the alphabet in some order to represent the substitution. This is termed a substitution alphabet. The cipher alphabet may be shifted or...

between cipher alphabets. In 1586 Blaise de Vigenère published a type of polyalphabetic cipher called an autokey cipher – because its key is based on the original...

The affine cipher is a type of monoalphabetic substitution cipher, where each letter in an alphabet is mapped to its numeric equivalent, encrypted using...

The pigpen cipher (alternatively referred to as the masonic cipher, Freemason's cipher, Rosicrucian cipher, Napoleon cipher, and tic-tac-toe cipher) is...

cipher originally used to encrypt the Hebrew alphabet. It can be modified for use with any known writing system with a standard collating order. The Atbash...

the encoder then uses as the start of the cipher alphabet. The end of the cipher alphabet is the rest of the alphabet in order without repeating the letters...

done according to the alphabet of the Baconian cipher (from the Latin Alphabet), shown below: A second version of Bacon's cipher uses a unique code for...

correspondence between individual letters of the alphabet and a specific musical note. There are also historical music ciphers that utilize homophonic substitution...

polyalphabetic cipher is a substitution, using multiple substitution alphabets. The Vigenère cipher is probably the best-known example of a polyalphabetic cipher, though...

The Theban alphabet, also known as the witches' alphabet, is a writing system, specifically a substitution cipher of the Latin script, that was used by...

The trifid cipher is a classical cipher invented by Félix Delastelle and described in 1902. Extending the principles of Delastelle's earlier bifid cipher...

Cipher runes, or cryptic runes, are the cryptographical replacement of the letters of the runic alphabet. The knowledge of cipher runes was best preserved...

The Playfair cipher or Playfair square or Wheatstone–Playfair cipher is a manual symmetric encryption technique and was the first literal digram substitution...

keys. The Caesar Cipher is one of the earliest known cryptographic systems. Julius Caesar used a cipher that shifts the letters in the alphabet in place...

cipher without a key (or, in other words, with a key of plain alphabet): The message is transformed into coordinates on the Polybius square, and the coordinates...

In cryptography, the ADFGVX cipher was a manually applied field cipher used by the Imperial German Army during World War I. It was used to transmit messages...

The Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication...

cryptography, a transposition cipher (also known as a permutation cipher) is a method of encryption which scrambles the positions of characters (transposition)...

The Two-square cipher, also called double Playfair, is a manual symmetric encryption technique. It was developed to ease the cumbersome nature of the...

be chosen randomly from the set of invertible n × n matrices (modulo 26). The cipher can, of course, be adapted to an alphabet with any number of letters;...

Latin-script alphabet consisting of 26 letters, with each having both uppercase and lowercase forms. The word alphabet is a compound of alpha and beta, the names...

substitution cipher that replaces a letter with the 13th letter after it in the Latin alphabet. ROT13 is a special case of the Caesar cipher which was developed...

The Lorenz SZ40, SZ42a and SZ42b were German rotor stream cipher machines used by the German Army during World War II. They were developed by C. Lorenz...

equivalent to Leon Battista Alberti's cipher disk except that the order of the letters in the target alphabet is not mixed. The tabula recta is often referred...

to the "Q" in the cipher alphabet). The entire message is then encoded according to this key. In addition to simple substitution ciphers, the cipher disk...

determine the next element in the keystream. This cipher was invented in 1586 by Blaise de Vigenère with a reciprocal table of ten alphabets. Vigenère's...

cryptography, a block cipher is a deterministic algorithm that operates on fixed-length groups of bits, called blocks. Block ciphers are the elementary building...

The Alberti Cipher, created in 1467 by Italian architect Leon Battista Alberti, was one of the first polyalphabetic ciphers. In the opening pages of his...