Given an appropriate external force, the movement of electrons is from negatively charged atoms to positively charged atoms. This flow of electrons is called current (I). The symbol “I” is used to represent current. The amount of current is the sum of the charges of the moving electrons past a given point.
An electron has a very small charge, so the charge of 6.24 x 1018 electrons is added together and called a coulomb (C). When 1 coulomb of charge
moves past a single point in 1 second, it is called an ampere (A). The ampere is named for the French physicist André Marie Ampère (1775–1836), one of the early founders of the science of electromagnetism, which he called electrodynamics. Current is measured in amperes.