The next Star Wars movie, Rogue One, comes to theaters this weekend, rocketing science fiction back to the top of the box office. “Science fiction” is the most popular way of describing the genre, but it’s not a one-size-fits-all term. Those inside the field use their own secret language.

Lisa Yaszek is professor and associate chair in the School of Literature, Media, and Communication and past president of the Science Fiction Research Association. She's published three books about the history of science fiction. A fourth is due out in 2018. In this edition of Tech+knowledge+Y, Yaszek describes the genre’s three categories and what makes them different, from the seriousness of Stanley Kubrick to the silliness of sharks.