The author calls the science of networks a science of real people, where stuff like friendships, rumours, diseases, fashion and music trends, commerce and finance are all involved. He explains how this science fits into the larger scheme of scientific progress and what it tells us about the world in our connected age. The book really covers two narratives: The history and development of the science of networks itself, plus the manifestation of network phenomena in the real world.
Chapters 2 to 5 investigate real world networks, chapters 3 to 5 consider the creation and implication of various models of networked systems, whilst chapters six (Epidemics and Failures), seven (Decisions, Delusions and the Madness of Crowds), eight (Thresholds, Cascades and Predictability) and nine (Innovation, Adaptation and Recovery) explore the spread of diseases, recovery, fads, politics, finance and organizational strength.
Some of the lessons of this thought-provoking book are that distance is deceptive and that in connected systems, cause and effect are related in complicated and sometimes misleading ways. In the latter regard, Watts discusses the many initial rejections that Kerouac's later very popular classic On The Road had to endure and the similar case of Rowling's first Harry Potter book.
The Further Reading section is arranged by chapter and provides recommendations of websites and books on that particular topic. The text contains tables, figures and some black and white illustrations and the book concludes with a bibliography and index. The Hidden Connections by Fritjof Capra and Small World by Mark Buchanan are similar books that I have found to be interesting and informative in this regard.