A galvanometer is a device used to measure small electrical currents. It consists of a coil of wire suspended in a magnetic field, with a pointer attached to the coil. When a current is passed through the coil, the magnetic field causes the coil to rotate, and the pointer indicates the current on a calibrated scale.

Galvanometers can be used as the basis for other measuring instruments such as ammeters, voltmeters, and wattmeters. They are commonly used in physics and electrical engineering experiments.