The pigpen cipher (also known as Freemason’s cipher) is the most popular secret writing alphabet. As reported recently, it has been used to encrypt gravestone inscriptions, treasure maps, certificates, mug inscriptions, beer labels and more. Today, I’m going to introduce ten more uses.

Blog reader Rosemarie Kohles from Coburg owns an old postcard written in a shorthand. Can somebody decrypt it for her?

The longest key ever publicly broken by exhaustive key search was 64 bits long. If you solve the cryptogram I introduce in this blog post, you can set a new record.

A recent article in the Sherlock Holmes fan magazine “The Baker Street Chronicle” reports on the relationship between the world’s greatest private detective and cryptology. In addition, it covers a few unsolved cryptograms from a real Victorian investigator.

In World War 2 the Germans used more than a dozen different cipher machines. A few more were developped but not used in practice. This article gives an overview.