An exploration into the nature of light--written in an engaging style for a wide audience. The author of dozens of books on science, Bova traces the history of the study of light, from Galileo's attempt to measure its speed, to Einstein's theory of relativity. He explains modern uses of light technology, including lasers, fiber optics, solar energy, and optical computers; and discusses biological and ecological aspects of light, and its role in the evolution of the earth. He concludes with some breathtaking possibilities on the scientific horizon. Illustrated.