The heat from a lightning bolt chemically combines the oxygen and nitrogen in the air with rain. The rain brings the nitrogen to the earth, where plants can absorb it through their roots. Many botanists believe that plant life on the earth could not exist without this natural fertilizer. Although the air we breathe contains nitrogen, we cannot absorb it like we absorb oxygen. We must obtain nitrogen from the plants and animals we eat.
Lightning is a tremendous discharge of static electricity.
During a storm, the earth's surface under a thundercloud becomes positively charged. Loose electrons gather in the bottom of the thundercloud, making it negatively charged. Since opposite charges attract, the ground and the electrons in the cloud attract each other. Because electric current always flows from negative to positive, the loose electrons in the cloud jump to the ground as lightning. Of course, lightning does not think before it strikes.