A voltmeter is an instrument used to measure the electrical potential difference, or voltage, between two points in an electrical circuit. It is typically connected in parallel with the component or section of the circuit being tested. The reading on the voltmeter indicates how much electrical energy is available to move charges through the circuit. Voltmeter readings are essential for diagnosing electrical issues and ensuring that devices operate within their specified voltage ranges. There are two main types of voltmeters: analog, which uses a needle and scale, and digital, which displays the voltage as a numerical value. Both types help users understand the performance of electrical systems.