What does it mean when an electrical device is 'grounded'?

Electrical grounding safety: If a wire inside an appliance shorts to the metal chassis (due to insulation failure), without grounding the chassis becomes energised at line voltage — touching it would cause electrocution. With GROUNDING: The third prong on a plug connects the chassis to earth ground via the building's grounding system; fault current travels the low-resistance path to ground, tripping the circuit breaker; the chassis voltage stays near zero. GROUND FAULT CIRCUIT INTERRUPTERS (GFCIs): Required in bathrooms, kitchens, and outdoor outlets — they detect even tiny ground fault currents (5 mA) and trip within 1/40 of a second, preventing electrocution faster than a circuit breaker.