The physical quantity that describes the transfer of electric current or charge is current strength, its symbol is and unit ampere (A).

The physical quantity voltage describes the work done to generate an electric current, i.e. to move charge carriers. The voltage between two points in a circuit is one volt ($U=1\text{V}$ ) when one joule of work is done to transfer a charge ($q=1\text{C}$ ) of size coulomb from one point to another ($A=1J$).