CODES AND CIPHERS.

PlayFair

Type: Substitution
> playfair cipher uses an array of 5x5 containing a keyword or phrase. The first step is to create a grid based on the key. The second step is to encrypt the letters of the message by selecting them in pairs.
Key: melons
(Note: grid size is 5x5 and i/j can interchange)
M E L O N
S A B C D
F G H I K
P Q R T U
V W X Y Z
Plaintext: VALENTINES
VA LE NT IN ES
Ciphertext: WSOLOUJOMA
WS OL OU JO MA