When discussing anything electrical that has to do with your house, you've probably heard the term GFCI. A ground fault circuit interrupter literally interrupts an electrical circuit when it detects that it may be flowing along an unsafe path like a person or water. It's used to prevent electrical shock or electrical fires. When electrical current on either side of the power source isn't equal (as would be the case if it were traveling to water or a human), the power shuts off. To reset it, the red button on the receptacle must be pushed. GFCIs can also be found in electrical panels.