The invisible web, or deep web, is estimated to be 500 times bigger than the searchable web and comprises databases and results of specialty search engines that the popular search engines can't index.
WebCite® is an archiving system for webreferences (cited webpages and websites), which can be used by authors, editors, and publishers of scholarly papers and books, to ensure that cited webmaterial will remain available to readers in the future. Authors
"reviewing and providing in-depth walkthroughs of today’s best products and services"; valuable because of plethora of new Web 2.0 software; explanation of how to use it gives clues as to if you would want to try new software.