Director
When producers David Brown and Richard D. Zanuck bought the film rights to Jaws, the search for a director began immediately. After a few of their first choices didn't work out, they turned to an unproven young fella by the name of Steven Spielberg who'd been making films since he was twelve years old. Brown and Zanuck had just produced The Sugarland Express, Spielberg's first feature film. They loaned him a copy of Jaws and he enthusiastically signed on. He was about 28 years old.
When Steve Met Bruce, a.k.a. the Great White Turd
His enthusiasm soon met its ultimate test as Jaws became Spielberg's first great trial-by-fire as a filmmaker. The shoot ran into one delay after another, mostly caused by problems with the mechanical sharks, affectionately nicknamed Bruce after Spielberg's lawyer, Bruce Ramer (source).
Designed by the guy who did the giant squid in 20,000 Leagues Under the Sea, the sharks (there were three of them, each used for different camera angles) turned out to be terrible actors. They got tangled in seaweed forests, their foam skin got waterlogged and warped, the electronic and pneumatic controls inside them got flooded with corrosive seawater, and on at least one occasion a shark sank right to the ocean floor 35 feet beneath the surface (source). Spielberg got so ticked at the shark that he started calling it "the great white turd," which probably just added to Bruce's stage fright.
Ultimately, though, the mechanical failures were a good thing. They forced Spielberg to be creative about how and when he used the shark, which in the end meant that Spielberg kept Bruce/GWT hidden for much of the film, relying on hints of the shark's presence—music, camera angles, floating barrels, body parts, etc.—instead of showing the shark itself.
The added mystery, suspense, and dread made the movie much scarier—a lot like the films of the greatest master-of-suspense director of all time. According to Spielberg, "The shark not working was a godsend. It made me become more like Alfred Hitchcock" (source). Hitchcock allegedly said, "There is no terror in the bang, only in the anticipation of it." He was right, of course. Waiting for the shark attacks is the really terrifying part of Jaws.
All's Swell that Ends Swell
Throughout the making of Jaws, Spielberg worried that the GWT (and the unforgiving Atlantic) would sink his career in its infancy. Even after the filming wrapped, he still had nightmares for months afterward that he was once again out on the ocean shooting Jaws. He didn't have to worry. Jaws became a huge hit, catapulting Spielberg to success and stardom, and coining the term "summer blockbuster." The boy wonder has gone on to enjoy one of the most staggeringly successful careers of any film director in history, with hits like E.T., Indiana Jones, Jurassic Park, Schindler's List, Amistad, War of the Worlds, Minority Report, and Saving Private Ryan under his belt. And that's just a partial list. We think you can relax now, Mr. Spielberg.