This is a book about languages that aren't real: those from countries that don't exist, alien languages, languages of mythological creatures and languages spoken in an imagined future or parallel universe. But they are also languages that are, to the highest degree, living on Earth thanks to their enthusiastic fans. Klingon, Valyrian, Syldavian, Na'vi, Lilliputian, Orcish – these are a few of more than 100 fictional languages that xenosociolinguist Yens Wahlgren delights in and unravels in The Book of Words. This is not a grammar book or a lexicon but rather an exploration through time and space, through worlds and universes arisen from the imagination, through pop culture and linguistic nerdship. Follow Wahlgren on a journey through the universes of Tolkien, Star Trek, Game of Thrones, Doctor Who and Marvel, from the complex and beautiful Elvish to the seemingly nonsensical yet surprisingly considered hoots of Pingu, and learn the creative and sociological value of constructed languages across the world (and beyond).