Where do you save the gamefiles you create inside Unity?

Now this is a curious question to everyone, but also a kind of habit if I should do it or not.
Basically, what I'm asking is that if everything you do in your game/project, do you save their inner files (Assets) on a separate folder on Windows? No, I'm not talking about the whole folder backup with the project settings, library, obj, etc etc. I'm talking only about the assets

Egx. In my case, I have a separate folder where I have my OWN created models using Unity, soundtracks and other things that I created by myself. On the other hand, I have my game project with everything in it using Unity.
It's a good practice to put the Scripts you've made, Animation Controllers, prefab models and other assets in the separate folder with your own things?

TL;DR - Do you put the assets in your game along with your own stuff that you made?
Cheers!