Sure, people will tell you that encryption is important to maintaining your online privacy, but how do you wrap your head around the concept? Mozilla wants to help. It's introducing a web-based game, Codemoji, that illustrates how ciphers work through emoji. Type in a phrase and Codemoji will both shift the letters and replace them with emoji. The challenge, as you might guess, comes when you get your friends to guess the meaning without turning to the Codemoji website. Mozilla stresses that you shouldn't use this as an honest-to-goodness secure communication system (it isn't). However, it should illustrate just why you'd want to protect your chats -- if your friends can't easily read your data, spies and thieves can't either.