Rationale for 'CommonProgramFiles'

Among the man开发者_如何学编程y special folder locations in Windows, the 'CommonProgramFiles' seems out of place. The description suggests that components (viz. DLLs) would be shared at that location.

It seems to me that a raw DLL storage location was the well-spring of "DLL hell." I had thought MS had moved towards the side-by-side cache, for native code, and the GAC, for managed code - both as a way to bury the age-old problem. So indeed is this 'CommonProgramFiles' a resurrected 'attractive nuisance' upon which to stumble? I notice that it has a predecessor 'CommonPrograms' that is available only on NT through XP.

Or perhaps there is some other motivation for the existence of this folder. Thoughts?

If the folder isn't used to store DLLs, perhaps then only 'CommonApplicationData' should be used, in lieu of 'CommonProgramFiles'?

CommonProgramFiles is e.g. C:\Program Files\Common Files; it's hardly resurrected, indeed the reverse: it's been around forever.

It's been with us for ages and MS doesn't make a habit of removing things because it breaks old programs.