I'm trying to understand better how scrum teams fit into actual organizations.

I understand that Scrum is only concerned with the structure of the scrum team - I'm just looking for some examples here as to who a project owner of a scrum team might actually report to. A director of engineering? Someone on the product side? Is there any convention here? I've heard the phrase "manager" thrown vaguely around with reference to scrum, does this refer to the person that the PO reports to? Thanks!