Okay kiddo, so the Health Physics Society is a group of really smart people who know a lot about how to keep us safe from things like radiation. They help make rules and guidelines for things like using X-rays, nuclear power plants, and even things like cell phones and Wi-Fi.
They also help teach people, like doctors and scientists, how to be careful when they use things that can give off radiation so that they don't hurt themselves or other people. They want to make sure that we are all healthy and safe!