In 1881, the International Electrical Congress, now the International Electrotechnical Commission (IEC), approved the volt as the unit for electromotive force. They made this decision because Alessandro Volta had invented one of the first batteries, which produced a reliable and consistent flow of electric current. The volt became so widely accepted that by 1890, it was included in international treaties and agreements.
The volt is used to measure electric potential difference (voltage), the difference in electrical potential energy between two points in a circuit. Voltage can be thought of as “electrical pressure” and is measured in volts (V) or (E). The voltage between two points equals the work done per unit charge moving from one point to another along an electrical conductor.
A volt is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI).