system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do TV shows and movies have opening credits if the credits are shown at the end?

Like why do TV shows have music playing in the background while they list all the opening credits when the credits play at the end anyways?
gpt
Opening credits are advertising, both for the major companies producing it and for the movie or show itself. It's part of the 'star system' where big names are promoted, and used to promote future works.

End credits are more about documenting the rest of the cast and crew.