Straightforward Linear Storyline; Selective Omniscient Narrator
Jaws' storyline is told in a straightforward, linear way. No flashbacks, no jumping around. It starts when the shark claims its first victim and it ends when the shark is destroyed and the heroes go home. Much of the tension (and the fun) of the film comes through its selective use of an omniscient narrator. At times we, the audience, are shown almost everything that there is to see.
The classic example: The only person who sees what happens to Chrissie Watkins is Chrissie Watkins, and she's not around to tell anyone about it. But we, the audience, get to see her horrific attack in excruciating detail (although we see nothing under the water). Later, as we're watching the rest of Amity's residents go about their lives, the dramatic irony—we know there's a giant shark lurking, while the cast of characters doesn't yet—ratchets up the tension and keeps us on the edge of our seats.