GFCI stands for Ground-Fault Circuit Interrupter. This type of outlet is also sometimes referred to as a GFI, and can be differentiated from regular convenience outlets by looking for the Test/Reset buttons built into the outlet. As part of National Electric Code, they are required at 120-volt outlet locations where moisture may be present in the home (i.e. outdoors, garages, basements, within 6 feet of any sinks in kitchens & bathrooms).
These type of outlets monitor the power going to devices (such as a hairdryer or small kitchen appliance), and will detect electrical current interruption (between the hot & the neutral wiring) to cut power to the outlet should water get on the equipment or outlet, thus preventing electrical shock.
Handy tip: If you are experiencing power loss to some of your outlets, it is possible you have a tripped GFCI outlet. If the “reset” button will not restore power to the outlet(s), one of our experienced electricians can help diagnose & repair the issue.