How much is revealed about the storyline, characters etc in film openings?

In a film opening, not much is revelaed. The whole point of the opening is to set the scene and give an insight to the characters, storyline etc. The opeing gives a preview of what is about to happen and normally introduce the main characters and give some main information to the storyline.

Forrest Gump: Opening 2 Minutes-
In the opeing to Forrest Gump there is little information given to the viewer and through the opening all the viewer sees if a white feather flying through the sky. The camera follows the feather until it finaly falls onto the main character. This then shows that we are going to find out more information about this character because we are lead to him by couinsidence but also purpose. This feather then leads us slowly into the storyline. I have examinded the clip below in this video with annotations. Please view the video in the best quality and be sure that annotations are on throught.
PLEASE WATCH VIDEO BELOW:

Please also see myself and Sophie Martins audience research about films and film openings. We asked questions regarding what should be revealed in an opening and what makes a good opening. Please watch the full video, their responses are also written below.