On December 11, 2020, just one day after the publication of Codebreaking: A Practical Guide, its authors, Elonka Dunin and Klaus Schmeh, got some news from fellow codebreaker Dave Oranchak. “[He] said ...

The 35-year-old saga of Kryptos, an enigmatic sculpture containing four encrypted messages outside the headquarters of the U.S. Central Intelligence Agency, recently took a bizarre twist.

Before we move into the meat of this article, let’s define a couple terms related to cryptography. The syllable crypt may make you think of tombs, but it comes from a Greek word that means “hidden” or ...