When it was first published in 1998 the ideas discussed in it were at the cutting edge of what was then known about the universe. In the intervening years there have been extraordinary advances in the technology of observing both the micro-and macro-cosmic world. Indeed during that time cosmology and the theoretical sciences have entered a new golden age. Professor Hawking is one of the major scientists and thinkers to have contributed to the renaissance. Hawking includes most of the recent developments in the field, many of which were forecast by him. At the same time he explains his complex theories through a fresh visual dimension. Over one hundred and fifty stunning color illustrations have been specially commissioned for this purpose, with computer images of three- and four-dimensional concepts which help the reader understand what have become popular mythic images of our century.