owners would be the responsible party, usually the top executive or managers

controllers would be the system admins or the IT teams

processors would be the programmers, data entry, help desk

custodians/stewards would be the management and IT teams doing backups and whatnot

Here a simple example for a library:

1. Owners (Library Director) decide which books should be available and set the rules for how they can be accessed. They also approve budgets for security measures and ensure compliance with policies.

2. Controllers (Head Librarian) determine how the book should be categorized, ensure it meets legal requirements (e.g., copyright laws), and manage user requests, like granting access or removing outdated copies.

3. Processors (Library Staff) handle the book based on the controller’s instructions, such as lending it to users, verifying records, and reporting issues like missing pages or unauthorized access.

4. Custodians/Stewards (IT & Maintenance Team) ensure the book’s digital file is stored securely, backed up regularly, protected with encryption, and follows retention policies. They also help during audits by providing records.