Reading some books there is something that i don't understand. Is the capacitors topics when they name a potential difference between conductors. As i know, Potential difference is the difference in electric potential energy per unit charge between two points.
So, talking about capacitors, the potential difference between conductors is:
a) The difference between the potential of each conductor.
b) The difference of potential between those 2 points: (conductor)· ·(conductor)