Access Control List

An ACL is a list of permissions attached to a resource that specifies which users, groups, or system processes are granted or denied access, and what operations they may perform. ACLs can be applied to files, network packets, API endpoints, or database objects.

While flexible, large ACL-based systems can become difficult to manage — modern systems often supplement or replace ACLs with role-based access control (RBAC) for administrative clarity.