God I feel old when I don't understand technology after a thorough reading (Dual Core)

First off, Honor in the alliance. Strength at Ironforge.

Now, this is how I feel old. Maybe you can explain to me this crap. What is Dual Core? I always thought Dual core was two processor chips working together and sharing the lode. Like Hard drive RAIDs and such. Isn't that what the Dual Core Xeon was? Now, I've been looking at Mobo and CPus, and when they say Dual Core, it doesn't seem to be talking about anything but one chip. Is it two core circuits on one block chip? what the hell? now I am confused after looking at the intel and dell site, and I haven't seen any dual core chip/mobo setup pics, under the chassis you know, to see if there is one or two sockets or such. And this makes me stupid. Stupid like drunk sorority sisters. I can't figure out the one thing... is it two chips on a board, or two cores on a chip on a board.?