History of trailers:
Trailers or previews consist of short clips from a film to be released in a cinema; or on DVD, with the aim of engaging with the audience to make them want to go and see the film.

The first film trailer was created in 1903 for the film 'The great train robbery'. This was seen as very important as it was one of the first short films/trailers released, and it inspired many others. I have also found another film created before that called 'life of a fireman', and this used cross cutting which inspired 'great train robbery', and I believe these films contributed to the conventions of short films and trailers, and they affected how we perceive films/trailers.

One of the earliest film trailers, what is also recognised by some as being the first trailer created was in 1912 for the serial 'The adventures of Kathlyn', the trailer was a preview of the next episode, this was astonishing as no one had seen a trailer before, and because of this the studios started to take notice of trailers. In 1913 the first trailer to be shown in a cinema was created in the U.S, this was a trailer of the musical 'The pleasure seekers'; which was to be shown on Broadway, this is quite unusual now as we don't really have trailers of musicals; and this was an advertisement for a musical. By 1916 Paramount studios became the first studio to start releasing film trailer, but only for their big films, but by 1919 Paramount had set up their own trailer division, creating trailers for every one of their films, and by late 1919 Paramount studios and other studios were looking for companies who specialise in making trailers, and who would spend their undivided attention on creating more effective advertising material for their films, and because of this the National Screen Service was set up. The NSS was created with the aim of overseeing distribution of promotional material of all studios, and up until the 50's they did that and most film trailers were created by the NSS, the famous old trailers created in the 50's and before were created by the NSS , but in the 60's the face of trailers changed. In the 60's textless, montage trailers and quick editing became popular, due to the arrival of 'new Hollywood', and the studios quickly picked up on this and began using the companies who produced trailers like this. Andrew J Kuehn opened a west coast office in Kaleidoscope, and this company focused on creating trailers using the new techniques from the arrival of 'new Hollywood', and he quickly became a major player in the industry because of the way he created trailers for the major studios. Many great trailer companies have been created by Kaleidoscope Creatives, such as The Cimarron Group, and Ant Farm. Keuhn and many other companies revolutionised the trailer and completely changed it with new modern, editing, and because of this it is easy to see how trailers have changed so much over the decades, early trailers were short, and consisted of little more than title cards, and stock footage, whereas now they are so much more elaborate and there are now so many variations of different types of trailers.

Trailers consist of short clips from a film, and are designed to attract the audience into watching the film. These short clips are usually the most exciting clips from the film, designed to engage the audience. The short clips are sometimes not in the order they're in the film, but they have been chosen as they convey the story of the film to the audience; and possibly attract a wider range of audience. Every film trailer has a time limit set by the MPAA, that is that the trailers can only be two and a half minutes and cannot exceed that, but each year every studio is allowed one exception; and they choose a particular film usually a major, big budget film which they know will be a blockbuster and very popular to exceed that time limit, and they choose the major films to exceed the time limit as it brings in the most revenue to the studio. Some trailers feature clips that are not actually in the film; but they're there as they are usually very exciting and attract the audience, and it makes the trailer much more unique and different to other trailers, and by adding extra clips it could maybe reach a different type of audience. One of the most famous films what used 'special shoot' trailers is Alfred Hitchcock's 'Psycho', which featured Alfred Hitchcock in it giving you a guided tour of the set of his film 'Psycho'; and talking to the audience eventually taking them to the infamous shower, because of him doing this the audience could understand why he did what he did in the film; and could relate to his ideas, which in turn attracted more people to the film.
Trailers are created by agencies but they are mostly cut at the studios, as they're the ones trying to sell their film, and know which clips are the best in attracting their audience. Also music which is on the trailers sometimes isn't featured in the film, sometimes music isn't on trailers but there usually is a soundtrack on trailers as that is a convention of film trailers. Voice-overs is also a convention of film trailers, but sometimes film trailers don't include voice-overs, but most do as it conveys the plot to the audience. The main reason for trailers is to attract the audience, and to sell the movie.

There are many techniques featured in trailers such as composition, and rating cards, but also there is awards for trailers. There are two award ceremonies every year for trailers; The Key Art Awards and The Golden Trailer Awards.