A multimeter, also known as a Volt-Ohm-Milliameter, is an electronic measuring instrument that is typically used to measure voltage, current, and resistance. There are analog multimeters that operate by moving a pointer to display the measurement, but today most multimeters are digital with an LCD that is used to display exactly what the measurement is.

A multimeter can cost as low as USD $10 and up to USD $400 for a really nice Fluke 87V. Unless you are planning on using the multimeter for professional purposes, I would recommend getting a low-cost multimeter like the ones shown in the following photograph:

The digital multimeter ...

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