Computer Instructor
Well, I had one event happen to me, where one lady had just bought a Apple IIc and complained that she was having problems with her monitor, so we told her to bring her monitor in, and we'd check it out.
So she brings her monitor in, and we plug it in, and it works without a flaw. We tell her that the monitor isn't the problem, and to bring her CPU in.
She stares at us blankly, and asks, "What's the CPU?"
Joe explains that it's the piece of equipment that all your devices plug into. So about twenty minutes later, she returns and walks in carrying the surge supressor.
When we explained to her the item that we needed her to bring in, she replied, "Oh you mean the keyboard!" (On Apple IIc's, the CPU box and keyboard are part of the same unit.)
And to make this all the more interesting, she was a gradeschool computer class instructor.