The Difference between a Trailer and a Teaser Trailer

I have researched the difference between a trailer and a teaser trailer in order to ensure that I am fully aware of what I need to do to fulfill my brief.
Teaser trailers tend to be shorter than trailers, the average length of a trailer is two and a half minutes to three minutes long where as a teaser trailer is usually just 30 seconds to one minute long. Teaser trailers contain less clips from the actual film itself and do not give away as much information about the plot. Often the teaser is filmed before the footage for the movie itself has even begun.
Trailers show a longer preview of the film and contain more shots than a teaser, these clips are often from the actual film itself. Trailers also give a more detailed outline of what the film is about and give away key details of the plot in an attempt to entice an audience to watch the film. Teaser trailers do not include much dialogue and some may not contain any but trailers do show dialogue throughout the scenes.
When I come to plan the production for my own teaser trailer I shall carefully consider and follow the conventions of a teaser trailer in order to makesure that I correctly follow my chosen brief.