The document discusses the history and evolution of horror films over time. It provides descriptions of influential early horror films from the 1920s-1980s like Nosferatu, Frankenstein, Psycho and Night of the Living Dead. It notes how horror films have changed from focusing on ghosts and monsters to incorporating themes like serial killers, zombies and supernatural possessions. More recent horror films from the 2000s emphasize realistic scenes and suspense to scare audiences by suggesting events could actually occur.