A slasher is a type of horror film that features a violent killer who stalks and murders his or her victims in a series of gruesome, often graphic scenes. The term comes from the idea that the killer uses a weapon (usually a knife) to "slash" their victims. These films typically follow a group of characters who are being stalked by the killer and must try to survive until they can be caught or defeated. Some well-known examples of slasher movies include Halloween, Friday the 13th, and A Nightmare on Elm Street.