What, according to Time Machine, are “System Files and Applications”?

Question

On Time Machine in Mac OS X (10.6), if you add /System to the exclusion list (items that should not be included in backups), it offers to exclude all "System Files and Applications" as well. What exactly does this list consist of? Does it include everything that's not in my home directory (inside /Users)? Is there any benefit in excluding some of these (say /System) and not the rest?

Answer 1

I want to hazard a guess and say that "System Files and Applications" is everything outside of your /Users home directory. Choosing to exclude one over the other would be pointless. If your goal is to choose between backing up your data versus backing up your computer, you should treat all system files as a whole unit, not as individual pieces. The UNIX philosophy, to which Mac OS X mostly adheres, scatters system files across many different directories, and excluding one over another will most likely result in an incomplete and nonfunctional computer backup.