A short film traditionally runs from 5-45 minutes and can be exhibited in many different environments as opposed to a cinema.
it does not have to be shown in the format of a film, a short film can be a extended advert , a music video a film trailer or a game trailer.
A link to an example of a extended advert which I have seen being screened before many films at the VUE cinema has been displayed below .
.jpeg)
Although some short films run before films in selected cinemas , it has become less common as the online age has further developed as most audiences are niche in which they have their own preferences as to what they wish to watch. 
Nowadays many short films are distributed via online sharing websites such as youtube , but as said early some still run before films , for example Disney Pixar created a short animated film titled "Day and Night" this was screened before every showing of Toy Story 3 which was a box office hit , as an audience member i did not grow tired or bored of Day and Night as i had already paid to watch toy story which is an animated film , so the short film before added to the build up of what Disney Pixar was capable of.
Before the release of the game "Red Dead Redemption" Australian director John Hillcoat commissioned and created a short film as a means of marketing the game. However the film was a "Machinima"animation which means all footage was shot on an in game engine (in game footage) to promote the product.
The short film was then later released and broadcast on FOX network and also popular video sharing website "Youtube". ( a link to the short film has been displayed below)
- Xan Brooks , Guardian 2010
Many recent music videos now include a narrative as opposed to only having audio entertainment the audience now has visual entertainment at the same time. however these type of short films usual portray the artist in a certain way, this can have both advantages and disadvantages , for example music artist "Snoop Dogg" music videos usually portray his lifestyle as being a gangster , living the fast life of riches , women or clothing when in fact it is probably quite different as he is a millionaire , some of these videos therefore give the wrong messages out as they are not what actually lead to a persons success
Sometimes two versions of the same song may be released however ones visual content differs from the other , one perhaps for online promotion and the other to be broadcast on television meaning it cant be as crude, although both may not promote a good message one may have censored swearing and violence
Below i have embedded two different videos used to promote the same song , one however portrays the artist in a worse way than the other does
