Radioactive waste refers to any material that contains radioactive substances, which are unstable atoms that emit radiation as they decay. This type of waste is produced by various industries and activities such as nuclear power plants, mining operations, medical facilities, and scientific research laboratories. The radioactivity in the waste can pose a threat to human health and the environment if not properly managed or disposed of. Therefore, it requires special handling, storage, and disposal methods to prevent harm to people and the ecosystem.