How do you catalog the series?
At first I thought that the anime was just that, just animation, without alternate origins. A lot of time later when I gained more experience, I realized that it was not only that, that many animes are adapted from other formats such as manga, novels, light novels and games
I currently catalog it like this:
Original anime: that exists only in the anime format
Adaptation: animes based on other formats such as manga, novel, light novel games, etc. that they were given an opportunity to have an adaptation for television
or internet; increasing its popularity
Franchise: series that are planned not only for anime format, but several formats are created based on the same idea, from the beginning