In the internet age, many of us are familiar with the concept of encryption to send data securely. But in fact, communicating in codes and ciphers have been around since long before the digital era. And so have scripts and glyphs that date back thousands of years and, to date, no one can figure out what they mean.
In this gallery, we look back at some of the most mysterious codes that remain uncracked. Click on the gallery to learn more.