Teaser Posters vs. Posters

There is a difference between teaser and normal posters as they are both created at different times of the film production. When a teaser poster is created, it is much the same as the teaser trailers. The film usually hasn't started being filmed yet and as a result, a release date is impossible to predict and broadcast. Therefore, a year of release is more vague and less open to critisism should the certain date not be reached. Sometimes, only 'Coming Soon' is used. It has an air of mystery and makes the audience want to know more; it teases the audience.

It is important that I am able to understand the difference between the two types of poster before even thinking about creating my own teaser poster. If I use the wrong conventions, it will not work, not to mention fit in with the brief.

I have found some examples of teaser posters on Google. They are:
The Dark Knight
Bella Swan - New Moon
Star Wars
The Crazies
Friday the 13th
At first glance, none of them give practically anything about the film away, only the genre really. They all have a main focus picture and small writing at the bottom. Some have a tagline at the top of the poster.