The thriller genre is known for being the corner of cinema that has some of the best use of suspense, tension and violence. In fact, the genre has a lot in common with horror, and often times the main separation between the two is a question of how much the villain drives the story. Thrillers often focus on topics of murder and crime, and is home to many of the greatest detective stories ever put to film.
Source:https://www.cbr.com/thriller-movies-actually-horror-films/