The concluding words of Unsolved! are a call to action. Craig Bauer, a US mathematician and editor-in-chief of the journal Cryptologia, ends his hefty history of cryptography by noting that even as he ...

Not all matters revolve around war and peace; love too can demand a veil of secrecy. "From a private collector, we have ...

Richard Bean does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their ...