“Yrv phvvdjhv vrqw fkliiuhv gh erxw hq erxw”. The world didn’t wait around for smartphone apps to communicate away from prying eyes. The Caesar cipher (like Julius Caesar) is an encryption method created by overlapping two separate alphabets: the classic alphabet and an encrypted alphabet that has been shifted, for example, three letters to the right. Alongside this somewhat rudimentary code, Caesar composed his messages in Greek, a language unintelligible to most Gauls of the day, but which the ruling Roman elites could read with ease.