In 1854, Sir Charles Wheatstone invented the cipher known as "Playfair," named for his friend Lyon Playfair, first Baron Playfair of St. Andrews, who popularized and promoted the cipher.

Here's your chance to crack ciphers similar to those Bletchley Park's codebreakers faced during World War II. Below, we present three ciphers of different levels of difficulty, from easiest to ...

Code- and cipher-breaking have been in operation for centuries. However, cryptanalysis – the art of deciphering encoded messages – took on a new importance during WW2 as British boffins ...