Ground Fault Circuit Interrupter (GFCI)
Since the 1970s, ground fault circuit interrupters (GFCIs) have saved thousands of lives and have helped cut the number of home electrocutions in half.
GFCIs are electrical safety devices that trip electrical circuits when they detect ground faults or leakage currents. A person who becomes part of a path for leakage current will be severely shocked or electrocuted. These outlets prevent deadly shock by quickly shutting off power to the circuit if the electricity flowing into the circuit differs by even a slight amount from that returning.
A GFCI should be used in any indoor or outdoor area where water may come into contact with electrical products. The National Electrical Code currently requires that GFCIs be used in all kitchens, bathrooms, garages, and outdoors.
*From: Electrical Safety Foundation International (ESFI)