Genre

Genre is used to group (categorize) similar groups of film, based on there conventions. There are multiple genres in film, such as: comedy, horror, action, romantic comedy and many more. Different genres attract different types of people. Those who go to watch comedy films, would tend to think that they are watching the wrong film if they saw many conventions of horror films (paradigms), like its settings, themes and situations that tend to be dark, eerie and gory  which are present through most horror films. Instead, they would expect to see stars that keep recurring in comedy films like Ben Stiller and Eddie Murphy, featuring on white backgrounds looking happy and funny. Also, other comedy paradigms include native events and moods throughout the film. (meet the fockers little fockers director : Paul Weitz)

Action films are another genre that share certain paradigms, that make it a unique genre from other types of film genres. They contains conventions like recurring icons, motifs and situations. The James Bond film, Casino Royal, contain many  that make it similar to other "Bond" films. The iconography of the sight down a gun barrel, instantly tells the user, that their film is going to be about action, as a gun is a traditional symbol of action films. Also, the iconography of the sight down the barrel of the gun, is repeated among, many action films.. The structure of the film is also a common convention, which consists of a huge series of pure action, in a gun fight, car chase, or an explosion. While these scenes are being shown, there is music being played in the background, which is just another convection of a typical action movie.
(James Bond : Casino Royal, Director : Martin Campbell)

Romantic comedy, is another genre of film, that has many conventions. One of the main paradigms is the stars of the films. Most romantic comedies are played by the same actors and actresses like Jennifer Anniston, Renee Zellweger and Julia Roberts, who play similar characters in similar scenarios.
(Bridget Jones Diary, director : Sharon Maguire) This then leads to another convention of romantic comedies, theme. Most romantic comedies start with a boy, who meets a girl, they get into difficulty, and end up happy at the end of the film. In the case of Bridget Jones Diary, the front covers of the film have the common convention of featuring the main star in the film. this leads the viewers to think that they are indeed watching a romantic comedy, and not a horror, because the same actors do not act in a horror film. Also the iconography of the front covers, make it apparent that it is a romantic comedy, with the use of pink, and hearts, which are often associated with romance.

Finally, horror films have very distinct conventions. The music is very dark, slow and jumpy, this gives the atmospheric tension. Psycho, is a classic example of a horror film, which uses music in order to create the conventional atmosphere that is expected in a horror movie. Another convention of horror movies is the iconography of the covers and characters. these are often black, red or dark colours, with blood stains on the cover. This kind of iconography would not been seen on a comedy film, as the black and red blood stains, are not perceived as being happy, funny things. the themes of horror films, is also another paradigm that brings the genre of horror together. Most films feature the same actors, which is another paradigm that the horror genre has over other genres.
(Psycho, director : Alfred Hitchcock)

In conclusion, many genres of film have lots of conventions that make then unique from each other. the main ways to group genres is through themes, structure, iconography, stars, settings and many more. Genres may share the same conventions, like themes etc, but that is what makes them different. The structure of a horror film, is much different from the structure of a action film, which is more lively, and fast paced. These differences between genres has led to many people prefer different film genres, and thats why there are so many different genres in the film industry today.