An Easter Egg is a term used to describe a hidden detail left in a movie by the filmmaker. This element could be a message, foreshadowing or call-back to another medium, designed to give the audience members sharp enough to catch, a thrill.
When it comes to finding Easter eggs in popular movies, you’re better off focusing on the director rather than the films themselves. Iconic filmmaker Stanley Kubrick was famous for filling his movies with hidden details, same with Quentin Tarantino.
Easter egg was coined around 1979 by Steve Wright, the then Director of Software Development in the Atari Consumer Division, to describe a hidden message in the Atari video game Adventure, in reference to an Easter egg hunt.