Horror Films are designed to frighten and to invoke our hidden worst fears, often in a terrifying and shocking finale. While captivating and entertaining us at the same time in a cathartic experience, horror films feature a wide range of styles from the earliest silent Nosferatu classic to todays CGI monsters and deranged humans. They are often combined with science fiction when the menace or monster is related to a corruption of technology, or when the Earth is threatened by aliens. The fantasy and supernatural film genres are not usually synonymous with the horror genre.