When measuring voltage with a digital multimeter (DMM), how should the meter be connected?

The meter should be connected in parallel when measuring voltage because this method allows the multimeter to measure the potential difference between two points in a circuit without disrupting the current flow. By connecting in parallel, the multimeter can accurately capture the voltage across the component or section of the circuit being tested while ensuring that the rest of the circuit remains operational.

Connecting a multimeter in series, which involves placing the meter within the current path, would measure the current instead of the voltage and could potentially disrupt the circuit operation. Similarly, connecting randomly based on convenience does not follow proper electrical measurement protocols, leading to inaccurate readings or circuit damage. The requirement of using both positive and negative leads is implied in the proper usage of a multimeter, especially for DC voltage measurement, but it does not fully capture the importance of the parallel connection for voltage measurement.