Western Trailer Conventions

In western film trailers, there are a few primary cliches. A standoff between sherrif and villain will occur, six bullets will be fired, even though revolvers can only fire 5 at a time. The setting with romantic, sweeping frontier landscapes or rugged rural terrain will be shown. The cowboy has a favored horse (or 'faithful steed') that he will be seen caring for at various points of the trailer. he also does a lot of riding on the aforementioned horse, no doubt to save someone tied up on train tracks in spagetti westerns. For example, Roy Rogers' Trigger, Gene Autry's Champion, William Boyd's (Hopalong Cassidy).  Westerns may extend back to the time of America's colonial period or forward to the mid-20th century, or as far geographically as Mexico. The lone, cynical cowboy who is trying to be honorable amidst a dishonorable environment. Usually he is lonely because he is a widower, or he was wronged.
A strong woman who is the voice of reason, (and probably the love interest) for the "hero."

Horror Trailer Conventions/ The Ring Task

The Ring is a prime example of how to use the horror conventions to make a successfully chilling trailer. One of the most obvious examples of the conventions being used is the creepy little girl as the antagonist. This is a trait that is shared with many other films such as The Omen and The Excorcist. For some reason children are scary and often look unkept if they are to star in a horror film. Phone calls illustrate that this is a film that follows the cliche's. Phone calls where bad news when the ominous "The call is coming from inside the house" was in When a Stranger Calls, and ever since a phone call can come from any source, no matter how unlikely it seems. A short trip to the local nuthouse seems to provide some insight as to what is happening, for asylums are full of victims of ghosts, ghouls and undead serial killers.

Fantasy/ Epic Conventions

The Lord of the Rings trilogy is a classic fantasy epic that displays many conventions ascociated with the genre. Conventions such as a grand battle, which was preluded by several samll battles, the concept of "Sword and Sorcery", and a range of near human protagonists and antagonists. In fantasy films there will always be a dark menace that needs to be stopped less there be darkness ruling the world. At the films primary battle scene which is viewed in snippets in the trailer, the good guys will be losing the majority of the time, until the very last few moments when an unusual amount of reinforcements arrive extremely quickly. There will be characters so powerful they gain time to say a quote before cutting to several fast shots of the aforementioned battle.

Romantic Comedy Trailer Conventions

The conventions of Romantic comedy trailers are very numerous. This includes the light hearted music as verious people smile at each other or the camera, the comic relief will wisecrack at one point. There is usually an awkward stare followed by another smile. A doubting mother will moan, and a father will say "go for it" in hushed tones. The rom-com trailer is home to all these and more cliches than you can shake an emotionally detached stick at. Even the intertitles will have these cliches, as they appear on screen with the actors leaning on their arms and smiling once again.
The trailer above shows many conventions that are ascociated with the genre including the awkward encounter with an attractive girl (in this case penelope cruz). There is a light hearted tune in the course of the trailer, with many other funny encounters, including a confrontation with a romantic/ trust issue, what is usually found in such a situation, only to be interrupted by "the funny guy". There is high key lighting to represent the lightened mood in a comedy such as this.