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 ...

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.

A cipher is a code used to protect information that is being stored or communicated, so that only people who are allowed to can access it. With this fun challenge, brought to you in partnership ...

1. An agent hands the text to a cipher clerk, who uses a code book to convert the words to four-digit numbers: 2. The clerk shifts one digit to the first group from the second, two digits to the ...