The differences between genre and sub-genre.

Genre is the theme or type of a piece of media, ie. a book or film etc. Genre is the main and most obvious one of these. Some examples of genres are horror, comedy, romance etc. Everything has a genre.

As the name suggests, a sub-genre is a secondary genre, that is generally less obvious but still has themes and ideas in the piece of media.

For example, a film might be an action film primarily, but there are scenes of horror or gore. A popular film series that has the genre of action but a sub genre of horror is the Resident Evil series, which revolve around a zombie apocalypse, and the main character, ALICE, saving the world from these zombies whilst sorting out her own troubles. The action involved in killing large numbers of enemies is all gun-scene fighting and special effects, and as this is the main part of the movie, the genre is action. However, because many scene have zombies eating people, and there are high levels of gore because of this, the sub-genre has been classified as horror.

In this way, all movies have a main and sub-genre, because it is difficult to make a movie with only one theme.