The concept of the password dates back to ancient Rome.
Roman soldiers used passwords—or ‘watchwords’—to identify themselves during night shifts and avoid being mistaken for enemies. These were passed from one sentinel to the next and even written on wax tablets by commanding officers. Fast forward a couple thousand years, and that same basic idea evolved into the digital passwords we type daily. From shouted Latin phrases to secret strings of characters, passwords have a surprisingly long and sneaky history.