What is lightning?

Lightning is best understood as an electrostatic current that travels between charged objects, specifically between clouds and the ground, or between clouds. This phenomenon occurs when there is a significant buildup of electrical charge in a thunderstorm, creating an imbalance that leads to the discharge of electricity. During this process, the air becomes ionized, allowing a current to flow, which is what we observe as lightning.

The immense energy released during this discharge produces not only the bright flash of light associated with lightning but also the sound of thunder as the rapid heating of the air creates pressure waves. Understanding this dynamic helps clarify why lightning is a specific electrical phenomenon rather than a thermal issue, sound wave, or electromagnetic radiation. Rather than being a form of thermal energy, lightning manifests primarily as a current of electricity. While it does generate thermal effects and sound, these are secondary to the primary nature of lightning as an electrical discharge.