Content on the Web that is not found in most search engine results, because it is stored in a database rather than on HTML pages. Viewing such content is accomplished by going to the Web site's search page and typing in specific queries. LexiBot was the first search engine to actually make individual queries to each searchable database that it finds (see LexiBot). Also known as the "invisible Web." Contrast with surface Web.continue reading
Some call it underground Web. See Yahoo Answers
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