The sun is the center of our system in more than a few ways. Without the Sun, human beings and life in general could not survive on Earth. Indeed, our solar system wouldn’t exist with the Sun.
The sun is a ball of plasma and chemical reactions. In practical terms, the sun is a thermal nuclear reaction on a major scale. The only thing that keeps the sun from exploding is the dense gravity holding it together. Below you’ll find information on sun that will shed a little light on the subject.