We’ve been hiding important messages since we first started sending them. Most ancient civilizations have their mysteries and they often included ciphers, codes, and other encryption systems in some form or another to prevent unauthorized persons from interpreting these messages.
The messages would be transported back and forth by speedy and stealthy couriers: the keyword being stealth (and the desire not to get caught). Because if the message was intercepted, the contents were likely to get into the wrong hands and be misused. To avoid this possibility, ancient codes and ciphers were crafted with such high levels of precision and perfection that many of them remain undeciphered to this day.
This is an encore of one of our previous lists, as presented by our YouTube host Simon Whistler. Read the full list!