Some people become very frightened during a thunder storm, but there’s really nothing to worry about. Lightning is the result of a collision between two electrical charges one positive, and the other negative either in two clouds or in a cloud and the earth. When the difference between the two charges becomes great enough, a great spark the lightning jumps between the two. Thunder is caused when that electricity has been discharged.
The air expands and contracts rapidly, and the air currents collide violently, causing the rumbling noise we know as thunder. You may have heard stories of people and things being struck by lightning. The spark of electricity hits the earth and is absorbed by it. Sometimes it does hit things like trees, but the like hood of it hitting a person is very small indeed, and there is no need to be frightened of a storm.