Learn to use the cipher utility with confidence. This Daily Drill Down walks you through using every cipher switch and shows you exactly what happens in the real world when you use these switches.

It’s been more than 25 years since Ron Rivest invented his RC4 stream cipher, and after all that time it’s still being used widely, which is something of an achievement in the crypto world. However, ...

A few months ago, GeekDad's Challenge of the Week was a lovely cipher about famous novels beginnings. I enjoyed solving it and that reminded me of a time where I was teaching younger students (12 to ...

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, ...

The Playfair cipher is an incredibLe code system that is both difficult to decrypt without a computer and easily solvable by hand. You might be familiar with the Cryptoquip in the comics section of a ...

What secret alchemical knowledge could be so important it required sophisticated encryption? The setting was Amsterdam, 2019. A conference organized by the Society for the History of Alchemy and ...

A recent study published in the journal Cryptologia presents what its author calls the Naibbe cipher, a manual substitution cipher system that, as he demonstrates, is capable of taking texts in Latin ...