One of the fundamentals that should be understood , before studying the methods of protection
against lightning , is the difference between the lightning arrestor and the lightning conductor. The lightning arrestor is usually used in electrical transmission and distribution . The lightning
arrestor is used to divert the lightning discharge current to the earth , 

before it could damage the equipment in the transmission or distribution system . The buildings are protected against lightning by using lightning conductors. It provides a low resistant path for the lightning flash , to carry its discharge current safely to the earth. Lightning rod , metallic rod that protects a structure from lightning damage by Intercepting flashes and guiding their currents in to the ground . Because lightning tends to strike the highest object in the vicinity , rods are typically placed at the apex of a structure.