These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Accidental Innuendo: Right as Chrissie is being eaten by the shark in the first scene, the guy she took with her to the deserted beach is almost passed out drunk on the sand, breathing heavily and whispering, "I'm coming...I'm coming..." Of course, given that he's wasted and he's chasing a girl, it may be deliberate.
And You Thought It Would Fail: Jaws was initially picked up as a script treatment by Universal Pictures, but ran into problems almost immediately. A rookie director who only had one other feature film — that bombed in theatres — to his name was chosen to direct the film. An actor who believed he was now box-office poison because of his prior work signed up as one of the main characters. Filming ran overbudget and overtime, with executives denying funding for key reshoots (which then had to be paid out of pocket). There were accusations that the practical effects were cheap and laughable, forcing the filmmaker to improvise by keeping it offscreen for most of the runtime. Yet, contrary to Steven Spielberg and Richard Dreyfuss' beliefs, Jaws became the first film to see wide-release distribution, became one of the highest-grossing films of all time and ushered in a new wave in American filmmaking.
Award Snub: Spielberg himself threw a fit in broadcast TV once he didn't get nominated for Best Director.
Even better when the shark pops up out of nowhere while Brody is tossing chum behind the boat and the leitmotif did not play. In every scene before that, the da-dun music kicked in warning the audience that the shark was coming.
Funnily enough, on first hearing the score Spielberg was quite bemused by how minimalist it was, and figured Williams had to be pulling a prank. Of course, he did initially hear it played on a piano, which probably made it sound dinkier than it would with a full orchestra.
Harsher in Hindsight: When you realize that the book and the film have contributed to making sharks endangered species by instilling such fear and hate of them to the point where the original author regrets writing it, then this property is horrible in an whole different way.
One-Scene Wonder: Susan Backlinie, in the very first scene. Still jaw droppingly terrifying decades later.
The movie has a wealth of these, thanks to the makers practice of finding colorful-looking locals for background roles. For many of these, this was their only (uncredited) film role, making them "One Scene In Their Whole Career Wonders." Examples include Donald Poole (Harbormaster Frank Silva), Steven Potter (Pipit's owner), and Carla Hogendyk ("Artist," a.k.a. the girl who shouts "Shark!" when it goes into the pond).
Ms. Kitner when she slaps Chief Brody. Technically she was also on the beach when her son dies, but her confrontation with Brody is unforgettable.
Special Effect Failure: Part of the reason the first film uses suspense and doesn't often show the shark is precisely because of this trope — Spielberg thought that the animatronic shark that they had was too unconvincing.
That, and it kept breaking down during filming, especially when they were out on the water.
The shark's appearance in the "you're gonna need a bigger boat" scene has not aged well since the film's release. It looks almost intolerably fake to modern audiences. It doesn't help that it gently pushes its head above the surface...whilst the characters react as though it had leapt out of the water.
Strawman Has a Point: The mayor isn't completely wrong that news of a shark could ruin the town — all "summer tourist" towns are extremely dependent on seasonal income. He's extremely wrong, however, in the degree to which he ignores the evidence. Also, his refusal to cut open the shark, possibly spilling the remains of it's latest victim (a young child), is completely right. Why they couldn't both agree to wait until everyone left and cut it open late at night (what Brody and Hooper do anyway) is anyone's guess.
On the other hand he did let the killing of one shark erupt into a media frenzy and basically declare mission accomplished without making sure it was even the right shark in the first place, which is why Brody and Hooper even wanted to cut the shark open.
Tear Jerker: Mrs. Kintner's confrontation with Brody over keeping the beaches open after Chrissie's death, resulting in her son being killed.
Chrissie's anguished screams of "God, help me!" can get pretty wrenching.
The death of Captain Quint. Godspeed, you salty old sailor.
The Problem with Licensed Games: The game mostly consists of swimming around harpooning innocent and harmless sea creatures. The fact that it's also based on the worst of the Jaws movies doesn't help matters.