I think I'm getting dumber

So the moped was just out of gas. Luckily, that's quite easy to fix =) I went to the moped shop and said, "Joe, my moped just died." "How much gas is in it?" "I don't know, but the gas light didn't come on." "Um, there's no gas light. That's the gas guage." That?? I honestly thought the gas gauge was some RPM-o-meter or something. It has numbers (corresponding to percentages) and I'd never seen that before, so I didn't even pay attention to that. At least now I know, right? I felt incredibly dumb though...