> Which is actually why the "files and folders" metaphor is apt.
It's a starting point, but I certainly wouldn't say it's the best metaphor that there could be. The idea of subfolders just doesn't make sense in a filing cabinet analogy, because you have to consider paper size - any folder which could fit into another folder is not going to be able to contain your regularly sized documents.
That said, I can't think of a better metaphor.
People understand hierarchy. That named file is in a folder in a particular drawer of a particular cabinet in a particular room of a particular building in a particular neighborhood in a...
What some people struggle with is recursive hierarchy where each step doesn't change the kind of container. I guess they never saw a Matryoshka doll when they were little.
> The idea of subfolders just doesn't make sense in a filing cabinet analogy,
Sure it does. The document is located in Building C, Sub-basement 2, Room 123, cabinet 415, folder labeled "Accounts". And a physical folder can certainly contain other folders. Nit-picking the analogy wastes everyone's time.
A better metaphor would be trees and branches. Which is already somewhat used for computing.