sentences:  The ciphers used in cryptograms were not originally created for entertainment purposes, but for real encryption of military or personal secrets.The first use of the cryptogram for entertainment purposes occurred during the Middle Ages by monks who had spare time for intellectual games.A manuscript found at Bamberg states that Irish visitors to the court of Merfyn Frych ap Gwriad (died 844), king of Gwynedd in Wales were given a cryptogram which could only be solved by transposing the letters from Latin into Greek.. Around the thirteenth century, the English monk Roger Bacon wrote a book in which he listed seven cipher methods, and stated that "a man is crazy who writes a secret in any other way than one which will conceal it from the vulgar."