Reece's Summary on Genre

Genre can be used to denote different types of storytelling extending across a range of different media such as fairy tales, plays and TV soaps; simply different types of storytelling. But it can also be used to refer to the classification of films into types such as horror, comedy, science fiction or thriller.
In film there are some clear definable genres:

Romance
Horror
Thriller
Science Fiction
Comedy
Fantasy
among others

And also other subgenres that could be made from a combination of any of the main genres and also more than a combination of 2. Most blockbuster films are a large variety of genres and subgenres due to the length of the film it helps to have a diverse way of telling a story to keep the audiences attention.
Genre does not rely simply on what's in a media text but also on the way it is constructed.
This can be important, for example, when distinguishing between a horror movie and a thriller, which can deal with similar subject matter, and look the same — lots of action set at night — but belong to separate genres, a horror film takes the audience into a supernatural place, where a thriller sticks to reality.


Steve Neale declares that 'genres are instances of repetition and  difference' (Neale 1980, 48). He adds that 'difference is absolutely essential to the economy of genre': mere repetition would not attract an audience.
This is true as for example horror has been one of the most varying genres over the years because a lot of things that scare audiences or entertain horror enthusiasts is based upon current events such as when people were a lot more scared of the super natural in the early years whereas now although supernatural is still prominent in current cinema the supernatural horror has changed itself so now there is less monsters in the woods horrors are more commonly set within homes and neighborhoods now and include a representation of real people with no supernatural  powers or include a more subtle kind of horror, also when there is a big natural disaster such as a volcano there are generally films based around that disaster closely followed after.




Also variations include where genres combine or hybrids as they are called. Rarely is a film seen nowadays that does include a multiple number of genres such as romance comedies or Sci-fi thrillers these give films a lot more depth and variation even between films with similar topics and are kept entertaining.




Rick Altman, in a 1984 article, proposed a
semantic/syntactic
approach to film genre. His aim was to ‘problematize’ the discussion of genre within film studies. He recognised that the development of film studies had seen a swing from ‘genre as history’ -- an approach which often used the film industries’ own terms to describe how genres changed over time -- to ‘genre as  semiotic) theory’ – an approach which largely ignored industry practices. Altman pointed out that genre (up until the 1960s) was often discussed in either ‘inclusive’ or ‘exclusive’ terms. Critics could refer in an almost tautological sense to a genre as comprising all the films that fulfilled a particular simple definition, e.g. westerns were films set in the American West between 1840 and 1900. But most analysis by scholars concentrated on a much more ‘inclusive’ list of ‘canonical’ films, which appeared to utilise the ‘essential’ elements of the genre. Altman initially proposed an approach which would combine the ‘inclusive’ and ‘exclusive’ via a general semiotic/structuralist approach. Thus the semantic approach to genre attempts to take abroad definition of a genre repertoire and to include for potential study all the films that appear to share the elements of the repertoire or ‘common traits’ such as characters, locations, shooting style etc. By contrast, the syntactic approach looks at the relationships between these elements and how they are structured in narratives. Altman’s example of this is the western in which the semantic approach concentrates on identifying the constituent elements and how they are presented, whereas the syntactic approach (e.g. via Jim Kitses, 1969/2004) concentrates on thematics such as the opposition of ‘East’ and ‘West’ or ‘garden’ and ‘desert’. In his 1999 book
Film/Genre
, Altman admits that the straight semantic/syntactic approach is lacking because it ignores the crucial key concepts that have since been re-inserted into film and media studies -- audience and institution. He adds a further ‘
pragmatic
’ approach which seeks to ask questions about exactly how producers conceive of genres and cycles etc. He also recognises that as ‘fluid’ groupings of elements, genre texts are open to a diversity of readings -- so audiences may, in effect, create and re-create genres through 'reading'. Earlier approaches had tended to see audiences as passive and to consider genre as formulae through which Hollywood ‘peddled’ its ideologies.