A GFCI (ground fault circuit interrupter) is an excellent electrical safety device
These fast-acting devices help protect against dangerous electrical shocks by interrupting the flow of power to the receptacle (outlet) when electrical current leaks from its intended path and flows to the ground (especially if that path is through another person!) This can occur when water, an exposed wire inside a metal appliance, or any other scenario creates an alternative pathway to ground.
Most outlets are protected by circuit breakers ranging from 15 to 20 amps. This is not enough to protect most people from severe shock and harm should their electrical outlets malfunction. Less than half a milliamp of resistance will “trip” a GFCI breaker, offering valuable protection to home and business owners.
Today, GFCI protection is required by the NEC (National Electrical Code) for receptacles installed in kitchen counter areas, bathrooms, unfinished basements, grade-level crawl spaces, garages, powered outbuildings, attics, and all outdoor locations. In addition, the installation of GFCI protection in existing homes that have a non-grounded, two-wire electrical system can provide an inexpensive safety upgrade.
Your home inspector should test the GFCI outlets located in these areas within your home or business, and report to you any malfunctions detected in the electrical systems.