The answer to 'how does GFCI outlet work' is that a GFCI (Ground Fault Circuit Interrupter) outlet is a special type of electrical outlet designed to protect against electric shock hazards. It continuously monitors the flow of electricity in the circuit and quickly shuts off power if it detects an imbalance, such as current leaking to ground. This helps prevent serious injuries or electrocution that can occur from faults or ground leaks.
GFCI outlets have a built-in sensor that compares the amount of current flowing into the circuit to the amount returning. If the two don't match, it means current is escaping through an unintended path, likely through a person. The GFCI will then instantly (in as little as 1/40th of a second) cut off the power to prevent electric shock. This makes GFCI outlets an important safety feature in bathrooms, kitchens, laundry rooms, and other areas where water is present and the risk of electric shock is higher.