The NEC (National Electrical Code) requires that all receptacles controlled by a GFCI be identified. That is why you get many stickers saying GFCI when you buy a ground fault circuit interrupter.
The code requires that ground fault circuit interrupters be installed in all areas where a human might come in contact with the earth, directly or indirectly. That includes, but not limited to, the kitchen, bathrooms, all outdoor receptacles, and the garage.
The GFCI works by monitoring the current in both wires, usually black and white, and if there is a difference of more than 6 mA, it assumes the difference is going through a human and shuts the circuit off. It only takes about 15 to 20 mA to electrocute you. Anytime you are standing directly on the earth. You are standing on one side of a 120 V circuit. Hope all that makes sense.

Interesting information but completely off topic.

UTUBE knows all

Yes …very interesting. I’m a widow learning how to do everything my husband took care of.
I learn a LOT from explainations like Dr Steven’s. You might consider it off topic.
I consider it excellent background information.
If you don’t like someone’s post just scroll on by.

You need to know where all your GFCI reset outlets are located because outlets are linked. Be sure to check in the Garage and out on your Lani.

Some of the resettable GFI outlets used by TV are very hard to reset with your finger.

An electrician who came to replace an outlet I had accidentally fried gave me this tip: Use a small blade screwdriver to bush the button back in when you reset the outlet. Works like a charm!

The outlets in the kitchen are daisy-chained to one with a GFCI. If you trip it, that is wher you reset them all. The bathroom outlets are on the outside outlet circuit.

. And preferably a non-metallic screwdriver just in case it slips past the button. :D :D

Sometimes
 

You can disconnect an outlet in the circuit and see if the circuit breaker does the same thing (won’t reset). If it resets, then the problem lies past that outlet in the circuit. Isolate the problem/outlet and inspect it. Once you have found the issue, look for touching wires, moisture etc.