The Deep Web; LIS professionals should know.

The Deep Web refers to any Internet information or data that is inaccessible by a search engine and includes all Web pages, websites, intranets, networks and online communities that are intentionally and/or unintentionally hidden, invisible or unreachable to search engine crawlers. The Deep Web is also known as hidden Web, Undernet, Deepnet or Invisible Web. 

Retrieved from: https://money.cnn.com/infographic/technology/what-is-the-deep-web/?iid=EL

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