Radiation is a type of energy that can come from different sources such as the sun or medical devices like x-rays. It can be dangerous because too much exposure to radiation can make people sick or cause cancer.
When something becomes contaminated with radiation, it means that it has absorbed some of this energy and could be dangerous to touch or breathe in. This can happen if there was a nuclear accident or explosion, for example.
If you accidentally touch something that has radiation contamination on it, the radiation can get inside your body and make you sick. This is why people need to wear special suits and masks to clean up areas where there is radiation contamination.
It's important to stay away from areas that have radiation contamination and listen to instructions from government officials or experts on how to stay safe.