distinguish words

There is little difference between ability and capability, although i have no doubt that someone will happen along who is willing to argue that there is. Capacity, however, although it can be used to mean the same thing as ability, can also mean simply the extent to which an artifact (such as a pot or a box) or a natural feature (such as a valley or a cave) can accomodate "filling." So i might say that he has the ability to run all day. I might also say he has the capability of running all day. I might say that he has the capacity to run all day. And, finally, i might say that the capacity of the room is twenty people.

Farad - A unit of capacity that will store one coulomb of electrical charge when one volt of electrical pressure is applied.