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Web Search Tools How to get the most out of search engines, web directories, and meta-searchers The “Invisible” Web Sometimes called the “Deep Web” Information that search engines cannot or refuse to index because it is locked up within databases
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Web Search Tools How to get the most out of search engines, web directories, and meta-searchers
The “Invisible” Web • Sometimes called the “Deep Web” • Information that search engines cannot or refuse to index because it is locked up within databases • At least 500 times bigger than the part of the web “visible” to search engines • Want to know more? Go to www.brightplanet.com • The bottom line: DON’T RELY ON GENERAL WEB SEARCH TOOLS FOR ALL YOUR INFORMATION NEEDS!
Built by humans Selective Evaluated Organized according to a scheme Most like a Subject search on ALICE Based on a thesaurus (pre-defined list of terms) Includes see & see also references Two types of searching: browse and keyword Can use various search techniques to focus results Not a “live” search Major advantage: user-friendly; can be easily browsed Major disadvantage: limited number of sites indexed Web Indexes, Directories & Review Sites Cannot find information located inside other databases, e.g., ALICE or Academic Search Premier.
Built by “robot” programs, not humans Not selective Not evaluated Results “arranged” but not organized Most like a keyword search on ALICE No thesaurus No cross-references Keyword searching only Must use keyword search techniques to focus results Not a “live” search Major advantage: can locate information “buried” inside web pages Major disadvantage: can bring back too many results Web Search Engines Cannot find information located inside other databases, e.g., ALICE, Periodical Abstracts, etc.
Results gathered by sophisticated search programs Not selective Not evaluated Results “arranged” but not organized Most like an “automated” reference librarian No thesaurus No cross-references Keyword searching only; search once – multiple results (in simultaneous meta-searchers) Can use limited keyword search techniques Not a “live” search Major advantage: saves time and keystrokes Major disadvantage: can’t customize each search Meta-Search Tools Cannot find information located inside other databases, e.g., ALICE, Periodical Abstracts, etc.
Points to remember… • It’s not all on the web! • Remember the Invisible Web • Directories vs. Search Engines • Use Advanced Search features • No search engine is perfect • Evaluate, Evaluate, Evaluate!