This course delves into linguistic typology: How do we classify languages? How much can languages differ from each other? What linguistic properties (if any) are shared across all languages? The course will demonstrate that, contrary to initial impressions, languages of the world do not differ arbitrarily and without limit. All human languages share a common core (universals). We must therefore explain why there are linguistic universals and along what parameters languages can vary (diversity). To do so, we will look at a wide range of linguistic phenomena across unrelated languages, many of which are endangered.