In Jackson's book he defines the capacitance of a conductor, "...the total charge on the conductor when it is maintained at unit potential, all other conductors being held at zero potential." I'm trying to get a more concrete definition in my head rather than the standard definition of capacitance being the ability to store charge. Can someone help me deconstruct Jackson's definition a bit further? From what my professor was drawing on the board, and from what he was saying ( in that, the capacitance is highly dependent on the geometry of the structure), I'm visualizing capacitance -from Jackson's- as a conductor in uniform charge distribution with respect to another nearby conductor. However, I'm also seeing this as very limited, if not wrong outright. I know somebody has the clarity I don't.