By convention, the direction of current corresponds to the direction positive charge moves (or would move if it could). In metal wires, positive protons don’t move and current is carried by negative electrons. This means the current direction is in the opposite direction the electrons move. This convention started back when Ben Franklin named electric charges $+$ and $-$, many years before the discovery of the electron.

Veterans: Some military electronic training programs (for example the U.S. Navy NEETS program in the 1960s) use the opposite convention, defining current to flow in the direction of electron motion, but we don’t use that here at Spinning Numbers. We follow the SI convention for current direction.

Created by Willy McAllister.

This is an updated version of the same video on Khan Academy. Thomson is now spelled without a “p” and the video has been shortened.