A lightning strike (or L~ stroke) is an electric discharge between the atmosphere and an earth-bound object. They mostly originate in the thundercloud and terminate on the ground, called cloud to ground (CG) lightning. A less common type of strike, called ground to cloud (GC), is upward propagating lightning initiated from a tall grounded object and reaches into the clouds. About 25% of all lightning events worldwide are strikes between the atmosphere and earth-bound objects. The bulk of lightning events are intracloud (IC) or cloud to cloud (CC), where discharges only occur high in the atmosphere.