Left and right are on the x-axis. The z-axis is where reversal of the object's image takes place. Lightning is a huge discharge. During this discharge, large amounts of charge flows from the clouds to the earth. This flowing of a charge is caused by a potential difference of millions of volts between the clouds and the earth.
Lightning rods protect tall standing structures from lightning.
They have the ability to protect tall standing structures because they are grounded. The lightning rods are grounded because they provide a path to the earth. The earth is electrically neutral and can absorb the charge carried by the lightning. Lightning rods are composed of conducting materials. Lightning rods are pointed which means they have a small radius of curvature.