Online Search Tools - Deep Web Search
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The Deep Web (also called the Deepnet , the Invisible Web , the Undernet or the hidden Web ) is World Wide Web content that is not part of the Surface Web , which is indexed by standard search engines .
Deep Web
There are several categories of search engine software: Web search or full-text search (example: Lucene ), database or structured data search (example: Dieselpoint ), and mixed or enterprise search (example: Google Search Appliance ). The largest web search engines such as Google and Yahoo! utilize tens or hundreds of thousands of computers to process billions of web pages and return results for thousands of searches per second [ citation needed ] .
Database search engine
This page contains a representative list of major databases and search engines useful in an academic setting for finding and accessing articles in academic journals , repositories , archives, or other collections of scientific and other articles. As the distinction between a database and a search engine is unclear for these complex document retrieval systems , see: the general list of search engines for all-purpose search engines that can be used for academic purposes bibliographic databases for information about databases giving bibliographic information about finding books and journal articles.
List of academic databases and search engines
99 Resources to Research & Mine the Invisible Web
College researchers often need more than Google and Wikipedia to get the job done.
The Invisible Web
What is the Invisible Web? How can you find it online? What makes the Deep Web search engines and Invisible Web databases so special?
100 Useful Tips and Tools to Research the Deep Web
By Alisa Miller Experts say that typical search engines like Yahoo! and Google only pick up about 1% of the information available on the Internet.
E-Print Network 3.0 - Advanced Search
Search thousands of e-prints in scientific and technical disciplines