Portable appliance testing (PAT) is a way to help keep you safe by making sure that the electrical things you use every day are safe. It's like a superhero who checks on all the electronic things you use, like your toaster, TV, and computer, to make sure they're not going to hurt you.
A person who does the testing is kind of like a doctor for your electronics. They use special tools to check the wires, the plugs, and other parts of your electronic things to make sure that they work correctly and won't cause any problems. They might also look at the instruction manual to make sure everything is being used properly.
Sometimes, the tester might put a special sticker or tag on the electronic thing to show that it's been checked and is safe to use. If they find any problems, they will let someone know so that the problems can be fixed before someone gets hurt.
So just like eating your veggies and wearing sunscreen, getting your electronics tested is one of the ways you can make sure you stay safe and healthy!