Windows XP Professional OEM & Retail?

Originally Posted by Stealth

OEM is original equipment manufacturer.

Basically they send you the disc and manual. There's no other difference between retail and OEM. And no, you still can only install it on one computer, legally.

Yeah, but he misses the chance to get the pretty Blue Box with the Windows logo.
Like they've said, the core product is the same. Only the retail packaging will be missing (you'll get a shipping box instead). The only time OEM vs retail matters is when buying hardware, where they might leave out wires and drivers in an OEM package.

Jam it back in, in the dark.

Originally Posted by Ulysses

If you wanted to cut costs a bit, you could opt for an upgrade rather than full version. I have heard that the upgrade contains the full OS except that you need a CD from an older OS to allow it to install. It doesn't actually read critical files off the old disc, rather it's just to prove that you are actually in ownership of the older software. Can't be 100% certain of this though, someone else here could confirm/deny.

I heard that works and works well, but I haven't tried to do so myself, I always had a OEM or (downloaded) full version of a Windows disc handy.

There's nowhere I can't reach.