Dive into the deep

Deep Web

From Wikipedia-
"The deep Web (also called Deepnet, the invisible Web, or the hidden Web) refers to World Wide Web content that is not part of the surface Web, which is indexed by search engines. It is estimated that the deep Web is several orders of magnitude larger than the surface Web."

From DeepWeb.com -
"Also known as the 'invisible web', the 'deep web' is a vast repository of web pages, usually generated by database-driven websites, that are available to web users yet hidden from traditional search engines. The 'spiders' used by these search engines to crawl the web cannot reach most of the pages created on-the-fly in dynamic sites such as ecommerce, news and major content sites."

From internettutorials.net-
"The deep Web has gotten a lot of press in recent years. The Web is becoming a complex entity that contains information from a variety of source types. It is much more than fixed Web pages. In fact, the part of the Web that is not fixed, and is served dynamically "on the fly," is far larger than the fixed documents that many associate with the Web. Some people incorrectly refer to this content as the "invisible Web," for reasons that will be explained below.

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