What makes a movie truly great and memorable? I bet 'plot' and 'characters' are the things that would first come to mind to many. But props have a big impact on a film's success and longevity as well. They capture the viewer's attention and interest even more than satisfying cinematography and a good script does.
Who knows if Star Wars would be such a cult franchise if they used simple swords instead of lightsabers? And Cast Away without Wilson? To this day, Tom Hanks claims that it's the one thing his fans shout at him the most. Willy Wonka's golden ticket, the Mockingjay pin in The Hunger Games – these props become symbolic not only in the movie but to fans as well.
Some props can just be cool background items, like the ice cream sandwich sofa in iCarly. Others are there to complement the character, to help us understand their personality better, like the hamburger phone in Juno.
But other props might also be central to the movie's plot. Sometimes, it's even in the title of the movie itself, like the One Ring in The Lord of the Rings or the Ark of the Covenant in Raiders of the Lost Ark. In the case of Cast Away, a prop can even become a character in the film, even if it is an inanimate object.
StudioBinder defines a prop as "an inanimate object that an actor interacts with in a film." On a movie set, there is a separate department that handles props, and it is run by the prop master. Props can be bought, but they're usually designed and made by the prop department. Nowadays, with 3D printing, it's much easier to make a prop, yet the heart of prop-making, according to Coffee House Industries, remains "in its artistic soul."
Sometimes, the prop department might do such a good job that viewers think the prop is real. Like the hoverboard in Back to the Future. Director Robert Zemeckis had many people believing it was a real thing in the '80s when he trolled fans in the behind-the-scenes special. The DeLorean, on the other hand, was a real car brand. However, by the time the movie came out, it was already defunct.
The main function of a prop is to contribute to worldbuilding. To make the audience believe that the world the movie is presenting is real and immersive. The creator of the Star Wars universe, George Lucas, understood this when he explained to his prop masters the need for a "lived-in" aesthetic.
The set designer for Star Wars, Roger Christian, said in a 2015 interview that Lucas' vision for scrappy science fiction was a novelty. "Most of the crew [...] thought science fiction should be like Flash Gordon. So George showed them Once Upon a Time in the West, Sergio Leone's great cowboy movie, and that was very dusty and very real. That was the look that we were trying to get. After that, I was aging the sets and throwing dust on them and making everything look very natural."
