New answers tagged credits
The Muppet Movie (1979) is obviously the first traceable true post credit scene instance but the older is 1963 with the James Bond film From Russia with Love, which was the first Bond film to show the ubiquitous "James Bond will return in..." at the end of the credits. (Source :Wikipedia)
The Muppet Movie (1979) was the first movie with a post-credit scene according to this Wiki page which lists all films with post-credit scenes.
The post-credit scenes are used as a way to make sure you watch the entire movie, credits and all. It also provides a break between the movie and the post-credit scenes. Sometimes they're "stingers", sometimes they're bloopers, sometimes they're additional comedic bits.
The scenes after the credits are usually "stingers". They were used as links or hookups to sequels. Now they are used as way to introduce characters and elements that will be present in a franchise.
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