The ampere (ˈæmpɛər , ˈæmpɪər ; symbol: A), often shortened to amp, is the unit of electric current in the International System of Units (SI). One ampere is equal to 1 coulomb, or 6.241509074e18 electrons' worth of charge, moving past a point in a second. It is named after French mathematician and physicist André-Marie Ampère (1775–1836), considered the father of electromagnetism along with Danish physicist Hans Christian Ørsted.
As of the 2019 redefinition of the SI base units, the ampere is defined by fixing the elementary charge to be exactly (coulomb), which means an ampere is an electric current equivalent to e19 elementary charges moving every 1.602176634 seconds or 6.241509074e18 elementary charges moving in a second. Prior to the redefinition the ampere was defined as the current passing through 2 parallel wires 1 metre apart that produces a magnetic force of 2e-7 newtons per metre.
The earlier CGS system has two units of current, one structured