The National Film Registry is the United States National Film Preservation Board's selection of films for preservation in the Library of Congress. The Board was established in 1988. Each year, 25 "culturally, historically, or aesthetically significant films" are preserved, to increase awareness for its preservation. To be eligible for inclusion, a film must be at least ten years old but it is not required to be feature-length, nor is it required to have been theatrically released.
Source: https://www.loc.gov/programs/national-film-preservation-board/film-registry/complete-national-film-registry-listing/
Short films I have seen
A list of the films added to the National Film Registry. (Updated 11/1/23)
The 50 Greatest Cartoons: As Selected by 1,000 Animation Professionals is a 1994 book by animation historian Jerry Beck, consisting of articles about, and rankings of fifty highly-regarded animated short films made in North America, as well as many other notable cartoons. It generated a significant amount of notice and discussion at the time, and is still commonly cited.
Library of Congress's National Film Registry
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