Background radiation refers to the low-level ionizing radiation that is always present in the environment. It comes from natural sources such as cosmic rays from outer space, radioactive materials in the earth, and even from our own bodies. This radiation is measured in units called microsieverts (µSv) and varies depending on location and altitude. Most people are exposed to background radiation daily, with an average dose of about 2-3 mSv per year. While it is a natural part of our environment, excessive exposure can pose health risks, which is why monitoring levels is important for safety. Sources like radon gas and cosmic radiation contribute significantly to these levels.