"Lightning is an electrical discharge caused by imbalances between storm clouds and the ground, or within the clouds themselves. Most lightning occurs within the clouds. Lightning is extremely hot—a flash can heat the air around it to temperatures five times hotter than the sun’s surface. This heat causes surrounding air to rapidly expand and vibrate, which creates the pealing thunder we hear a short time after seeing a lightning flash. Lightning protection systems are used to prevent or lessen lightning strike damage to buildings. They protect the internal electrical components of a building, helping to prevent fires or electrocution. Lightning protection comes in the form of a lightning conductor, usually a metal rod, mounted on a building to protect it from lightning strikes. The system will intercept a strike so if lightning hits the building, the lightning rod will be hit first, causing the strike to be conducted through a wire, and passing through to the ground safely."