Understand the concept
A complete electrical circuit needs a source, a conductive path, a load, and a return path. A switch can open or close that path. Voltage is potential difference; current is charge flow; resistance limits current.
A wall switch normally interrupts the ungrounded (hot) conductor, not the equipment grounding conductor. Grounding and bonding have specific safety roles and are not normal return-current paths.
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Practice task
Learn to identify line, load, neutral, and equipment ground on a *de-energized training diagram* before touching hardware.
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