Thus a shift of 1 moves "A" to the end of the ciphertext alphabet, and "B" to the left one place into the first position. As the key gets bigger, the letters shift further along, until we get to a shift of 26, when "A" has found it's way back to the front.What does the number 26 mean in the affine cipher?
The number 26 represents the length of the alphabet and will be different for different languages. The Affine cipher can be broken using the standard statistical methods for monoalphabetic substitution ciphers.What is the modulus for each letter in a cipher?
Each letter is represented by a number modulo 26. Though this is not an essential feature of the cipher, this simple scheme is often used: To encrypt a message, each block of n letters (considered as an n -component vector) is multiplied by an invertible n × n matrix, against modulus 26.How to decrypt a Caesar cipher?
Decrypt key is nothing just the knowledge about how we shifted those letters while encrypting it. To decrypt this we have to left shift all the letters by 2. That was the basic concept of Caesar cipher. If we see this encryption technique in mathematical way then the formula to get encrypted letter will be: c = (x + n) mod 26