"120 volts" refers to the standard voltage level used in household electrical systems in many countries, including the United States. This voltage is commonly used to power everyday appliances, such as lamps, toasters, and televisions.
In electrical terms, voltage is a measure of the electric potential difference between two points. A voltage of 120 volts means that there is a potential difference that can drive electric current through a circuit, allowing devices to operate efficiently and safely.