Conventions of Trailers

• Trailers always have the green screen at the very beginning that states that the 'preview has been approved for appropriate audiences'. This screen usually lasts for about 5-7 seconds to ensure that the audience had time to read it properly.
• The title/logo of the institution that produced the film conventionally appears after the first green screen. This shows the audience clearly the company that produced the film and allows them to briefly promote themselves/claim recognition for the film.
• Often the trailer will begin with an establishing shot to display the films location instantly or to emphasise the significance of the location. If not then the trailer could begin with a shot of the main character or a character that plays a significant role in the films narrative. 
• Fast fade to black transitions are conventionally used between shots in films with a horror or thriller genre. 
• Many film trailers use voiceovers that talk over the shots. These voiceovers could either be from one of the main characters giving their insight and setting the tone of the film. On the other hand it could be a voiceover of somebody different outlining the films plot. In horror film trailers they often use a mans voice and make him speak slowly or creepily to increase tension. In romance trailers the stereotypical cheesy Hollywood voiceover is sometimes used. 
• In films of a horror or thriller stereotype, the music often starts off as quite upbeat and relaxed as the main characters are living happily and the antagonist hasn't appeared yet, but when the antagonist comes in and bad things start happening, the music gets more dramatic and intense. It often gets louder throughout the trailer. 
• Trailers will almost always include the release date or season e.g. "This Summer"
• In Romance films with teens the trailer conventionally includes shots of the school and shots of big groups of friends.
• All trailers include titles and the title of the film appears at the end of the trailer in a memorable font so that the name of the film stays in the audiences mind. 
• Comedy trailers often use an upbeat song often a popular pop song or a song with lyrics relating to the film. Romance trailers often use love songs. 

Teaser Trailers:

• Teaser trailers are shorter and don't include as much as theatrical trailers, as they are designed create excitement for a film without giving much away. 
• Teasers create mystery whereas Theatricals promote. 
• Teasers usually last up to 1 minute 30seconds, trailers can last up to 2 minutes 30. 
• Theatrical trailers are shown closer to the films release date.