The sun, upon which this planetary system depends, has been a constant source of wonder and curiosity to man. In this text the various avenues man has taken toward understanding the sun are outlined. The ramifications the sun's distance has on our calculations of time and light, the importance to human life of the sun's comparative stability, and the uses to which man has and will put the sun are clearly examined here. With the increasing interest in solar energy, this is a text which may suggest to many young readers a career in a new but vital field. And for those with a merely academic interest in man's environment, a text which asks many meaningful questions and answers them.