Description
The Playfair Cipher was created in 1854 by Charles Wheatstone, and named after Lord Playfair for promoting its use. Initially, it was rejected by the British Foreign Office for appearing complicated. Later, the military began to use it for being relatively quick to use with no necessary special equipment. They used it in the Second Boer War, WWI, and WWII- to lesser degrees in the latter wars.
Using this cipher involves employing a Polybius Square (based off the 24-letter Latin alphabet) and letter pairs- or digraphs.