Why is there lightning?

Lightning is caused by static electricity generated by water vapor in cumulonimbus clouds, which leads to voltage difference between clouds and the ground. When the voltage difference is large, it will break through the air, making the air instantly expand and explode, releasing heat and light. Light is lightning, and the loud noise from the expansion explosion is thunder.

According to the different terrain and meteorological conditions, lightning can be generally divided into three types: hot lightning, front lightning (hot front lightning and cold front lightning) and terrain lightning.