Voltage and Current
Voltage is an electric force that causes free electrons to move from one atom to another.
Just like water needs pressure to force it through a hose, electrical current needs some force to make it flow. A volt is the measure of electric pressure. Voltage is usually supplied by a battery or a generator.
The scientific symbol for voltage is the letter "E" dating back to the early days of electricity when it was called "Electromotive Force." Electricians and wiring books use the letter "V" for "Volts."
Current is electricity in motion.
Electrical current is measured in amperes, or "amps" for short. Amperes measure the number of electrons that can flow through a material like a conductor. Amps are similar to the amount of water flowing through a hose in a certain amount of time. Instead, it is the amount of electricity flowing through a wire. The scientific symbol for amps is the letter "I."