Darth Vader proclaiming he is Luke Skywalker's father is among the images that will be preserved by the US Library of Congress as part of its National Film Registry.
The 25 films selected this year include The Empire Strikes Back, the 1980 sequel to Star Wars which many critics and fans consider the best of George Lucas' six Star Wars films. Empire shocked moviegoers with the revelation that masked villain Darth Vader was the father of hero Skywalker.
The goal of the registry, which began in 1989, isn't to identify the best movies ever made, but to preserve films with artistic, cultural or historical significance.
Librarian of Congress James H Billington has chosen each of the films, culling them from suggestions by the National Film Preservation Board and the public. More than 2,100 films were nominated by the public in 2010.
Original copies of films picked for the registry are kept safe and available for viewing by future generations.
This year's selections also include Saturday Night Fever, John Badham's 1977 disco musical starring John Travolta as Tony Manero, the working-class youth known for his impressive moves on the dance floor at a Brooklyn nightclub.
As in the past, the selections show the Library of Congress has a sense of humour. Two broad comedies, Airplane! the 1980 disaster-film spoof, and The Pink Panther (1964), starring Peter Sellers as the bumbling Inspector Clouseau - were tapped for preservation.
While Billington enjoys the popular films selected for the registry, he takes more satisfaction in unearthing lesser-known titles with lasting significance.
"The most interesting thing for me is not seeing something I like make the list, but getting educated by the list that comes out of this process," he said.