Google is just the tip of the iceberg of the web. Remember, the internet is a network of networks. Boeing has their own hidden web that is only accessible to Boeing employees. Hospitals save their medical records within their own network of networks. Even library catalogs are invisible to Google! In order to access these hidden websites, you must use different search engines such as CWU's OneSearch or the search engines from library databases.
For an overview of the different parts of the web, how we access it, and more on this beautiful infographic, go to http://www.elixirofknowledge.com/search/label/Dark%20Web
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