Google, the largest search database on the planet, currently has around eight billion web pages indexed. That’s a lot of information. But it’s nothing compared to what else is out there. Google can only index the visible web, or searchable web. But the invisible web, or deep web, is estimated to be 500 times bigger than the searchable web. The invisible web comprises databases and results of specialty search engines that the popular search engines simply are not able to index.
Do you think your local or university librarian uses Google? Sure, but certainly not exclusively. In order to start researching like a librarian, you’ll need to explore more authoritative resources, many of which are invisible. Note: Although some of the following resources are visible and indexed, they have all been included here because of their authoritative nature.