Genre refers to categories of artistic works that are defined by similar styles or conventions. Genres are formed over time as new ones emerge and old ones fade away, and works can fit multiple genres by combining conventions. In film theory, genre describes how films are constructed based on similarities in narrative elements, which are often borrowed from theories of literary genre criticism. Films can be categorized by their setting, theme, mood, format, or target audience, and genres can further branch out into subgenres or combine to form hybrid genres.

1. Genre is the term for any category of literature or
other forms of art or entertainment, e.g. music,
whether written or spoken, audial or visual, based on
some set of stylistic criteria. Genres are formed by
conventions that change over time as new genres are
invented and the use of old ones are discontinued.
Often, works fit into multiple genres by way of
borrowing and recombining these conventions.
In film theory, genre refers to the method based on
similarities in the narrative elements from which films
are constructed. Most theories of film genre are
borrowed from literary genre criticism. Besides the
basic distinction in genre between fiction and
documentary , film genres can be categorized in
several ways.
The setting is the milieu or environment where the
story and action takes place. The theme or topic refers
to the issues or concepts that the film revolves
around. The mood is the emotional tone of the film.
Format refers to the way the film was shot (e.g.,
anamorphic widescreen) or the manner of
presentation (e.g.: 35 mm, 16 mm or 8 mm). An
additional way of categorizing film genres is by the
target audience.
Film genres often branch out into subgenres, as in the
case of the courtroom and trial-focused subgenre of
drama known as the legal drama. They can be
combined to form hybrid genres, such as the melding
of horror and comedy in the Evil Dead films.