Wookiees come from Star Wars, introduced in the 1977 film as the tall, furry species of Chewbacca, Han Solo's co-pilot. Their language, Shyriiwook, is made entirely of growls, roars and whines, so a single short clip can read as a greeting, a warning or a question depending on its pitch. Fans clipped individual Wookiee lines as soundboards grew popular, and this questioning growl spread as a shorthand reaction for bafflement. It is still used because the emotion is clear even to viewers who have never seen the films.