Language is humanity's most spectacular open-source project, and the internet is making our language change faster and in more interesting ways than ever before. Online communities spread new slang and jargon with dizzying speed, while social media is a vast laboratory of words where we can watch language evolve in real time. Bringing enthusiasm and a sense of wonder to the subject, Gretchen McCulloch explains what shaped your preference for "LOL" or "lol," what emoji have in common with physical gestures, and why animal memes like lolcats and doggo caught on.