A multimeter is a universal measuring device. You can measure voltage, current, resistance, as well as wire breakage.
You can use special measuring instruments such as an ohmmeter, ammeter, voltmeter for each of these measurements. For example, a voltmeter is used to measure voltage, an ammeter measures amperage, an ohmmeter is used to measure resistance, but the universal instrument for measuring voltage, current, and resistance is a multimeter.
So, ohmmeter + ammeter + voltmeter = multimeter.
