For the Vikings, lightning was produced by Thor as his hammer struck an anvil while riding his chariot across the clouds. Lightning is a discharge of electricity. This extreme heating causes the air to expand at an explosive rate. The expansion creates a shock wave that turns into a booming sound wave, better known as thunder. Thus the name thunderstorm.
Lightning can take place in several different areas of a thunderstorm.
Sometimes lightning can jump from one cloud to another or to the surrounding air. Most of the lightning we see appears as a single line of bright white light. However, there are several other types of lightning that can occur. Ball lightning fireballs have been reported in some tornadoes and vortices have also been associated with floating spheres of ball lightning, which sometimes disappear with a loud explosion, suggesting they, too, contain combustible material. Basically the fire burns at the center of the tornado where the air is relatively calm.