A slasher film is a genre of horror films involving a killer stalking and murdering a group of people, usually by use of bladed tools. Although the term "slasher" may occasionally be used informally as a generic term for any horror film involving murder, film analysts cite an established set of characteristics which set slasher films apart from other horror subgenres, such as splatter films and psychological horror films.

Critics cite the Italian giallo films and psychological horror films as early influences. The genre hit its peak between 1978 and 1984 in an era referred to as the "Golden Age" of slasher films. Many slasher films released decades ago continue to attract cult followings. The slasher canon can be divided into three eras: the classical (1974–1993), the self-referential (1994–2000) and the neoslasher cycle (2001–2013).