1. Introduction -- 2. From Julius Caesar to simple substitution -- 3. Polyalphabetic systems -- 4. Jigsaw ciphers -- 5. Two-letter ciphers -- 6. Codes -- 7. Ciphers for spies -- 8. Producing random ...

J K Rowling’s The Hallmarked Man features the Pigpen Cipher, a centuries-old code once used by Freemasons and revolutionaries. Here is its history.

Caesar cipher is a very simple encryption method and is easily cracked if one studies the frequency of repeating letters. To improve the strength of the encryption method a more complex key could be ...

Mozilla has launched Codemoji as part of its Encryption Matters campaign to teach people about privacy on the web. The Codemoji website provides an easy way to share an emoji-encoded message with ...