In a Multiplicative cipher, each character of the alphabet is assigned a zero-based value (A=0, B=1, etc.), and a key coprime to the alphabet length is chosen. Each character value is multiplied by this key, then reduced modulo 26 to find the substituted letter. For example, M has value 12; with key 3, 12 * 3 = 36, and 36 modulo 26 = 10, which maps to K. This cipher is closely related to the Affine cipher.