The 35-year-old saga of Kryptos, an enigmatic sculpture containing four encrypted messages outside the CIA headquarters, just ...

The message is called the plaintext because it is the unchanged source information. Example: The cat ran away. The secret message generated is called a cipher or ciphertext and it is the encrypted ...

You can make a message secret in countless different ways. One common way is to use a substitution cipher, in which one letter is substituted for another. Another is to employ a transposition cipher, ...

Cryptography puts the “crypto” in cryptocurrency. It has existed much longer than our digital age and has evolved like languages over the centuries. One of the most famous uses was developed by Julius ...

Learn how to implement a classic substitution cipher in C! This step-by-step tutorial walks you through encoding and decoding messages by replacing each letter with another according to a fixed key. A ...

Ars' own Julian Sanchez has deciphered a code embedded into the TV show Fringe. Bad Robot, the production company that created the Fox TV show, has been integrating puzzles and easter eggs into shows ...

Hannah handed me a piece of paper with the following string of letters. “Each letter stands for another one,” said Hannah. “Ooh, a substitution cipher!” I thought. But I was stumped. “Is this just one ...