Question

What is the lighting? How is it caused?

Answer 1

1. Lightning: The difference of charge between two adjacent clouds or clouds and the ground becomes very large. The insulation of air breaks down and electrons flow through the air to neutralize this charge difference. This generates a huge electric spark in the sky, called Lightning.
2. When a charged cloud passes over an uncharged cloud, the uncharged cloud obtains an opposite charge.
3. Later when two oppositely charged clouds come close to each other they attract and strongly combine to produce large amounts of heat, light, and sound thus causing lightning.