A multimeter, also known as a volt-ohm meter or VOM, is a portable electronic device used to measure various electrical quantities such as voltage, current, and resistance. It typically has a display screen and a set of probes that can be attached to different parts of an electrical circuit to make measurements. Multimeters are commonly used by electricians, electronics technicians, and DIY enthusiasts to troubleshoot electrical problems and to verify the proper functioning of electrical components and circuits. They can also be used to test batteries, fuses, and other electrical devices.