Communicate in a language only you and your friends can understand! Protect your diary from snooping siblings. Share your secrets with a BFF. Guard your texts from unwanted eyes. Create the lingua franca for your own fantastical secret world! Expert language creator David J. Peterson (inventor of languages for Game of Thrones, the Marvel Universe, and more) guides you as you create your own secret languages, codes, ciphers, and hidden messages. From simple cyphers to entirely new alphabets, master the skills of secret communication, whether it's written, drawn, or spoken. By the time you're finished reading, you'll be able to share messages memora vosak laz vos otihoe vosecchi! ("that no one will be able to understand!").

Introduction -- From letters and numbers to ciphers -- From ciphers to codes -- From ciphers and codes to a language -- Final thoughts.