I gained access to this book free, via the sponsor of our non-profit's first year of operations, or I would not have bought it. It must certainly be in the library of any university or college with ambitions to educate those who will lead the next wave moving us toward Web 3.0 and Web 4.0. It is however reasonably priced and I recommend it for both library acquisition and deep reader purchase. The publisher has been responsible about posting useful information (see inside the book, the second active link below the cover on this page) so I urge anyone asking that this work be acquired, at this price, print and attach the table of contents to their requisition. The book is very well-organized with ample white space and excellent illustrative graphics and figures.