As best as I can tell this is actually a file named "Bar.pm" in a subdirectory named "Foo".

Same thing. The directory is considered to be part of the filename, really, as the distinction is often meaningless in practice, and files' actual names cannot contain forward slashes anyway, so there's no ambiguity.

Can this sort of thing go on to multiple levels? Like, could we have a module named "Utterly::Completely::Foo::Barred::Up" that would be defined in the "Up.pm" file located in the "Utterly/Completely/Foo/Barred" subdirectory (of a member of @INC, I guess)?

Yes. To give a random example from my system, App::Prove::State::Result::Test lives in a file named Test.pm in a (sub)directory called App/Prove/State/Result.

And, is that the only place where such a module could be found, or could it also be in a file of a different name and/or in a different subdirectory?

Yes, that's the only place where such a module could be found, though @INC may of course contain several places where Perl will look.

In reply to Re^3: difference between packages and module by AppleFritter
in thread difference between packages and module by Anonymous Monk

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