Film trailers

http://www.youtube.com/watch?v=hKEp7WYrMmY
This is a trailer for The Ten Commandments (1956), which is immediately noticeable as being very short by modern film trailer standards at just over 1 minute. The directors name is announced first as opposed to today where often the main stars will be boasted. There is also the boast of it being "intact" and "uncut", as films were often very heavily edited back then from their original intent.

http://www.youtube.com/watch?v=13EUXqIwDkQ
Here we see the trailer for The Good, The Bad and The Ugly exactly ten years later (1966), which is drastically different at almost 3 and a half minutes, longer than most modern film trailers and showing off some of the more spectacular battle sequences such as the infamous bridge battle. The scenes are much less edited than Ten Commandments and the hanging scene from the trailer is almost intact, only cutting off to avoid a spoiler.

http://www.youtube.com/watch?v=YDGw1MTEe9k
In 1973 this trailer for The Exorcist again demonstrated change for film trailers, the trailer is once again shorter than a typical modern trailer though one interesting feature to note is how the more vile scenes are absent entirely, possibly to secure wider distribution, as the suspenseful nature is now much more prevalent rather than simply displaying the most prominent shocks or spectacular action scenes.

http://www.youtube.com/watch?v=d1XmZ9_ckdw
This trailer for Conan the Barbarian again shows changes to the overall aesthetic and structure of trailers, with far less actually occurring story wise but a greater emphasis for the voice over narration and the showing off of its main star, Arnold Schwarzenegger.

http://www.youtube.com/watch?v=eajuMYNYtuY
Finally this trailer for Terminator 2 shows much more emphasis in general, with title cards and narration being put to their full usage and using music from the film to match the sequence on screen. One noticeably problem though is that the trailer actually gives away a twist in the finished film, which is obviously a problem.