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

Some ciphers have simple keys, others, complex ones. The key for a cipher used by Augustus Caesar, some 2,000 years ago, was simple enough: The receiver just had to shift the alphabet one position.

The Caesar cipher is one example of a larger class of techniques called substitution ciphers. These replace every letter in a message with something else according to a translation.

Most everyone has experience with simple encryption, like substitution ciphers that alter the letters of the alphabet using a particular rule, like A=Z, B=Y, C=X, and so on.

You can decipher all substitution ciphers using that method, not only simple shift ones like Caesar's. That will only take longer but will be more interesting, too, as you will need more than one ...

If they crack the code, which is a fairly simple substitution cipher (or not), it reveals a phone number where they can leave their contact information.

The message was encoded with a simple substitution cipher, one of the most basic ways to encrypt something. In a cipher of this type, the alphabet is scrambled, with each letter in the alphabet ...

The Egyptians: Early Encryption and Hieroglyphs As early as 1900 BCE the ancient Egyptians used simple substitution ciphers to encode messages in their hieroglyphic writings. While their use of ...