Fantasy, Adventure, Science Fiction
Surprised science fiction wasn't first on our list? It might have been if looks were the only way genre struts its stuff. Genre is more than skin deep, though, and at its narrative core, Star Wars is a fantasy.
In his analysis of the film, Jonathan Rosenbaum noted, "If Kubrick's central subject [in 2001 ] was intelligence, Lucas' is predicated on blind instinct…"
The characters in Kubrick's 2001 —the epitome of science fiction films—seek intelligence and knowledge as a means of power and then apply reasoning to solve their conflicts. Star Wars doesn't follow this science fiction mode, and its characters apply faith and belief in an external Force as a means to resolve conflict.
The Force is described as a mystical "energy field created by all living things" and what "gives a Jedi his power." The powers of a Jedi are never explained as anything but supernatural, and they act like magic.
The Jedi practice is more like a religious belief than a study of the universe, and the film's Jedi master, Obi-Wan Kenobi, has more in common with Merlin or Gandalf than a scientist. The result: the film's insistence on trusting the Force is in the same wheelhouse as the fantasy trope of believing in the supernatural.
Other story tropes more familiar to the fantasy genre than science fiction include a young hero on a quest, rescuing a princess from a tower, and the dark lord in need of a thrashing. Substitute a "dragon" for "Death Star" and "spaceship" for "trusty steed," and you see the fantasy within.
With that said, Star Wars does dabble in science fiction. The film is populated with space ships, extraterrestrials, and interplanetary settings. All around, the technology is more advanced than anything we have currently developed, and people utter phrases like, "It's the ship that made the Kessel run in less than twelve parsecs." Parsecs? Kessel run? That certainly sounds science-y (and fictional).
However, science fiction stories typically focus on technological advances in our society or the societies of imagined futures. While Star Wars certainly has advanced technology and an imagined society, neither of those are its focus.
The film's rapid-fire pacing sets the alien society at the periphery, and we never get a chance to see how it operates. Also: the film is not about our future. As the famous opening suggests, it took place a long, long time ago.
Now let's consider the lightsaber. In a History Channel documentary, scientists point out that the lightsaber can't exist. Sorry, everyone. If the lightsaber emitted lasers, then the blades would pass through each other, which hardly makes for an exciting duel. If the blades were plasma, the lightsabers' magnetic fields would repel each other, making for excellent dueling—but it would have to be 200 million degrees to slice through a door.
In the end, these scientists have put more thought into the lightsabers tech than the film did. In Star Wars, technology and societies don't need to be explained; they simply need to be.
Ultimately, the science fiction elements of Star Wars exist more as set dressing. Consider them a visual upgrade to the fantasy core of the film—Fantasy v2.0.
Some people have played moderators and dubbed Star Wars "science fantasy" along with other stories that have elements of both genres such as Edgar Rice Burroughs's A Princess of Mars and later entries in the Final Fantasy video game series. You can go that route, too, if you wish.
What Time Is It?
Adventure time! Star Wars also draws inspiration from Hollywood's golden age of adventure, when handsome actors played swashbucklers who included sword fighting and derring-do on their resumes.
It is easy to see Star Wars' adventurous heritage. The purest example comes when Luke and Leia are cornered by stormtroopers with an inoperable bridge between them. Thinking quickly, Luke latches a grappling hook to a structure above. Leia kisses him and says, "Good luck!" right before the two swing across the chasm. That's so Errol Flynn.
Like any good adventure, the movie provides escapism for the audience. You know the heroes won't die during their escapades, so you're free to relax and enjoy the excitement. Luke and Han perform courageous deeds that should have gotten them killed several times over, but no matter the odds, the obstacles, or the setbacks, they manage to come out okay.
This is because Star Wars is a card-carrying member of the adventure genre—that or the Imperial Stormtrooper Marksmanship Academy needs to step up their game.