[QUOTE=asterion]
Well, the idea is, if the OS needs to be reinstalled, you just wipe the small partition that contains the OS. The larger partition is what holds all your data. It’s a pain afterwards, since you have to reinstall all your programs to set the DLLs, though of course you could just use an image. (I assume the same is true, more or less, on a Mac.)
[/QUOTE]
a) We hardly ever have to reinstall the OS. A single installation of the OS is nearly always going to last you until the next version of the OS comes out and you install over the old one (archive and install, most commonly) and keep going. More likely than not, you’ll do a daisy-chain of such installations (10.4, 10.5, 10.6, 10.7, 10.8) over the years and retire the computer without ever having to reinstall the OS.
b) When we do reinstall the OS, we don’t have to reinstall our applications. A reinstall can also use archive-and-install, leaving all your settings and applications fundamentally untouched (except the Apple-branded apps, I guess). Then you’d do Software Update to bring all the freebie decimal-point updates up to current (which would bring your Apple-branded apps to current status).
c) Quite aside from which, about 92% of our applications don’t need to be “installed”. If I have two Macs and one has an app that I’d like to have running on the other Mac, I can just do a file copy of the app (or application folder) and it works on the destination computer. We don’t have .dll files sprawled all across creation, nor do we have a registry. The application “file” is actually a disguised folder containing the library files, or, if it’s an application folder, they’ll be in the folder. So wherever you copy it, everything you need is there with it. In the remaining 8% of Mac apps, there may be some essential low-level deelybopper that has to be installed with super-user permissions; these apps do come with an installer, and for these it’s true that you can’t just do a file-copy procedure to copy the apps. Even there, archive-and-install will often preserve whatever has been installed of that nature, so even then a reinstallation of your apps may not be necessary.
It’s extremely rare that a Mac user really needs to reinstall an application. I figure 80% of the applications on my current computer were simply copied over from my previous computer (so their installation date predates the manufacturing date of my current computer). Probably 55% of them date back to pre-OS X operating systems on that older computer, so they were never installed under OS X on the old computer either. Maybe 20% of them were copied over from the computer before that one and therefore were never actually installed on this computer or the previous computer. And yes, a tiny handful came from even older computers. You install a Mac app once, it’s generally the last time you’ll ever have to install it, unless you’re at someone else’s computer and installing it for them. They’re permanent, like furniture: when you move, you take it with you!
:mad: :smack: :rolleyes: 
