Microsoft Metaphors

[Declan McCullagh]

What are the best metaphors to use when talking about a browser and an
operating system? Is the combination like a car and an engine, or a car and
a roofrack? A pair of gloves?

Or is it even useful to talk about a browser/OS metaphor in the case of
Microsoft, since IE has been glued into the operating system in the form of
.DLLs? Might that be more like the wheels of a car?

-Declan