The Zodiac Killer's cryptic messages weren't just taunts to police — they were a twisted throwback to his first victim, according to an independent investigator who says he's cracked the code and ...

A comprehensive educational cipher toolbox for encryption and decryption, featuring both classical and modern cryptographic algorithms — now with a built-in MCP (Model Context Protocol) server for AI ...

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.

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

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 envelope arrived at the San Francisco Chronicle in November 1969 without a return address, its directive to the recipient, in handwriting distinctively slanted and words unevenly spaced, to ...

Despite its beauty, or maybe because of it, the state of California has been a magnet for history’s worst serial killers. Still unknown is the identity of the serial killer who terrorized Northern ...

A coded message sent by a brutal serial killer who has never been caught has been cracked more than 51 years after it was sent. This story originally appeared on Ars Technica, a trusted source for ...