This is an updated version of a previous book by the same authors. The Invisible Web is the name they give to that part of the Internet that is ignored by or denied to ordinary information seekers. Their basic argument is that, paradoxically, as more information becomes available online, more of it is moving out of reach. The overwhelming majority of searches are done through general purpose search engines such as Google and Yahoo. While these are very efficient and valuable, they choose to ignore or are denied access to many sources of information. If the typical searcher only uses these general purpose search engines, then what the search engine does not index is essentially invisible.
The Invisible Web is a huge repository of resources that can be available to searchers who make the effort. Much of it is proprietary to company databases, some is paywalled, and huge amounts are restricted by password access. The typical student searcher goes first to Google, then to Google Scholar, then to Wikipedia and finally to a library resource. Other researchers have found that YouTube is used as a major resource. This underpins the second, non-technical definition of the Invisible Web: that part of the Internet that searchers choose to ignore because it is beyond their research abilities. The authors believe that all students should be taught first to be aware of it, and then how to access it.
The remainder of the book does just that. Part of it addresses the technology-driven aspect. There is a chapter on vertical and niche search tools. These focus narrowly on specific topics or needs and index both the Surface Web and the Invisible Web. Parts discuss social networking and how to access the deluge of information generated by its users. One trend noted by the authors concerns issues of ownership and intellectual property. As competition between the various social media sites heats up, restrictions are being placed on access to the content, so the Invisible Web becomes a bit more invisible.
Then there is the world of mobile apps. Mobile devices do not have the same display capabilities as desktop machines so restrict what they show, thereby inadvertently increasing invisibility. Personalisation is another problem. Search engines try to map user needs by remembering their past searches, so the results returned will be different on the same query from two users. The difference increases invisibility. The worry is that, as technologies evolve, they hide as much as they show.
Eliminating the non-technical reasons for invisibility is the other major focus in this book. There is a chapter on information-seeking behaviour of today's students that examines how students are responding to the information sources available to them. Another chapter surveys how institutions are tackling the information literacy shortfall and gives recommendation for incorporating the Invisible Web in teaching. The book finishes with a useful list of resources for mining the hidden parts of the web.
Overall this is an excellent book for anyone concerned about information literacy and how to maintain the research skills of students at all levels.
