I apologize for my very basic question, but I cannot find a straight forward answer anywhere. I want to know "Physically, what are volts". I understand that amps are a count of electrons passing a point in one second. I know the formula for Ohm's law, but that still doesn't answer the question in my mind. I've read that a volt is a measurement of pressure, or the measurement of potential difference of charges between two points. Ok, what physically causes that difference? Is it that there are more electrons at point A than at point B and they want to move to point B? If that is the case, then how does the voltage stay the same once some electrons have moved to point B? Also, how is the voltage regulated in a battery. I see that it stays the same at all times. How is that?