Jaws is a 1975 American thriller movie directed by Steven Spielberg and based on Peter Benchley’s 1974 novel of the same name. In the movie, a giant man-eating great white shark attacks beachgoers on Amity Island, a fictional New England summer resort town, prompting the local police chief to hunt it with the help of a marine biologist and a professional shark hunter. Take a look below for 30 more fun and interesting facts about Jaws.

1. The movie stars Roy Scheider as police chief Martin Brody, Robert Shaw as shark hunter Quint, Richard Dreyfuss as oceanographer Matt Hooper, Murray Hamilton as Larry Vaughn, the major of Amity Island, and Lorraine Gary as Brody’s wife, Ellen.

2. The screenplay for Jaws is credited to both Benchley, who wrote the first drafts, and actor-writer Carl Gottlieb, who rewrote the script during principal photography.

3. Jaws was shot mostly on location on Martha’s Vineyard in Massachusetts. The movie had a troubled production, going over budget and past schedule.

4. As the art department’s mechanical sharks suffered many malfunctions, Steven Spielberg decided to mostly suggest the animal’s presence, employing an ominous, minimalistic theme created by composer John Williams to indicate the shark’s impending appearances.

5. Universal Pictures gave Jaws what was then an exceptionally wide release for a major studio picture, with over 450 screens, accompanied by an extensive marketing campaign with a heavy emphasis on television spots and tie-in merchandise.

6. Considered one of the greatest movies ever made, Jaws was the typical summer blockbuster, with its release regarded as a watershed moment in motion picture history.

7. Jaws was the highest grossing movie of all time until the release of Star Wars.

8. Along with Star Wars, Jaws was pivotal in establishing the modern Hollywood business model, which revolves around high box-office returns from action and adventure pictures with simple high-concept premises that are released during the summer in thousands of theaters and supported by heavy advertising.

9. In 2001, Jaws was selected by the Library of Congress for preservation in the United States National Film Registry, being deemed, “culturally, historically, or aesthetically significant.”

10. According to writer Carl Gottlieb, the line, “You’re gonna need a bigger boat,” was not scripted, but was ab-libbed by Roy Scheider.

11. According to director Steven Spielberg, the prop arm looked too fake in the scene where Chrissie’s remains are discovered, so instead, they buried a female crew member in the sand with only her arm exposed.

12. Robert Shaw couldn’t stand Richard Dreyfuss and the two argued all the time, which resulted in some good tension between Hooper and Quint.

13. Over 67 million people in the United States went to see Jaws when it was initially released in 1975, making it the first summer “blockbuster.”

14. According to The Making of Steven Spielberg’s Jaws documentary, the shooting star that appears during the night scene where Brody loads his revolver was real, not an optical effect.

15. Director Steven Spielberg named the shark “Bruce” after his lawyer.

16. Composer John Williams conducted the orchestra during the 1976 Academy Awards, so when it was announced that he won the Oscar for Best Score, he had to run up to the podium to accept his Oscar and then run back to continue conducting the orchestra.

17. Three mechanical sharks were made, each with specialized functions. One shark was open on the right side, one was open on the left side, and the third was fully skinned. Each shark cost approximately $250,000.

18. Martha’s Vineyard, Massachusetts, was used as Amity Island primarily because even 12 miles out to sea, the sandy bottom was only 30 feet down, allowing the mechanical shark to function. Residents were paid $64 to scream and run across the beach as extras.

19. When the shark was built, it was never tested in the water. When it was put in the water at Martha’s Vineyard, it sank straight to the ocean floor. It took a team of divers to retrieve it.

20. Author Peter Benchley was thrown off the set after objecting to the climax.

21. In the actual Jersey Beach shark attacks of 1916, which Hooper mentions in the movie, the sequence of attacks is similar to that of the movie: a swimmer in the surf, a dog, a boy, and the leg of a man in a tidal slough.

22. Most of the movie was shot handheld to best countermand the ocean’s swell.

23. Director Steven Spielberg played first clarinet for the beach scene.

24. Brody’s dog in the movie was actually Steven Spielberg’s real dog, Elmer.

25. Director Steven Spielberg shot roughly 25% of the movie from water level to provide the viewers the perspective as if they were treading water.

26. Steven Spielberg said that when he first read the novel, he found himself rooting for the shark because the human characters were so unlikable.

27. Author Peter Benchley had mentioned that if he had known about the actual behavior of sharks, he would have never written the book.

28. The average summer tourist population of Martha’s Vineyard before the movie was released was approximately 5,000 people. After it came out, the population went up to 15,000.

29. To create the sound of a drowning woman during post-production, Susan Backlinie was positioned, head upturned, in front of a microphone, while water from above was poured down into her throat.

30. During the display in which Richard Dreyfuss and Robert Shaw compare battle scars, Roy Scheider lifts up his shirt to reveal an appendix incision. This wasn’t a prosthetic, but Scheider’s own scar.