How does one crack the world’s most famous code? The breakthroughs on Kryptos provide a guided tour through the cat and mouse game between code makers and code breakers that has defined information ...

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

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 ...

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, ...