What exactly does ACL mean? (Sharepoint)

Question

We talk about ACL in SharePoint and that document library inherits ACL by default, and we may chose to have separate ACL for document library, etc.

So, when we talk about ACL, are we referring to List of Groups/Users we navigate to Manage Permission link on site or library?

I tried searching on web but couldn't find any insight on this.

Answer 1

ACL - Access Control List.

Ok, that's not very helpful. It changes on context, but basically it's the list of permissions for an asset that allows you to assign rights to users and groups of users (and in stranger cases machines and other non-human things).

In your case it's the Windows groups, and individual users that may access Sharepoint, and the permissions for those users (Can read, can upload a file, etc.)