I've seen this term bounced around a lot on hardware lables but I have no ideas what it is. What's OEM stand for? What's the difference between it and regular hardware products?

For hardware this means you get all the hardware e.g cables etc, and drivers.  What you don't get is additional software like demos or games, also it is often that you don't get original packing but a brown box instead.  Buying OEM hardware is a good way of saving a bit of money.  If you get OEM software be careful, as often they are quite a bit cheaper but once it has been installed on one machine it dies with that machine and can not be installed in any others even if removed from the original machine.