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Search Engines

Search Engines. Presentation by Erica Strassler. What is a Search Engine?. A tool that lets you explore databases containing text from hundreds of millions of Web pages.

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Search Engines

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  1. Search Engines Presentation by Erica Strassler

  2. What is a Search Engine? • A tool that lets you explore databases containing text from hundreds of millions of Web pages. • When the search engine software finds pages that match your search request (Hits) it presents them to you with brief descriptions and clickable links to take you there.

  3. What sets them apart? Been around for more than 2 years searching made easy as possible large searchable databases, help info, look and feel conductive to searching The Big Six Search Engines • AltaVista • Google • HotBot • Lycos • Northern Light • Yahoo

  4. Bix Six: What they Do Best(An Overview) AltaVista: obscure facts and figures full Boolean and case-sensitive searching Google: thoroughness general searches (link popularity method) HotBot: multimedia files simpler interface than AltaVista

  5. Bix Six Overview (cont.) Lycos: multimedia searches phrases containing stop words Northern Light: simultaneous web search and “special collection” database Yahoo: most detailed web directory

  6. AltaVista • Developed 1995 at Digital Equipment Corporation • Owned by CMGI but Compaq owns small stake as well • created by spider program called Scooter Weaknesses: • good at finding new web pages but bad at weeding out dead ones

  7. Google Created in 1998 by Stanford doctoral students Larry Page and Sergey Brin The name Google is a play on the word “googol” coined in 1938 largest database: more than 1.2 billion Web pages Only search engine that indexes full text PDF files Weaknesses: Boolean operators and power search fairly limited

  8. HotBot Launched in 1996 by Wired Digital; acquired in 1998 by company that operates Lycos Powered by Inktomi -largest, most frequently updated database -name from Lakota Indian legend search customization features (rivals AltaVista)

  9. Lycos • Developed in 1994 by Michael Mauldin at Carnegie Mellon; now owned by Terra Lycos, a Spanish company that also owns HotBot • Name from latin “wolf spider” • Powered by the FAST search engine • multimedia searches Weaknesses: • ignores all Boolean operators

  10. Northern Light • Launched in 1997 by a small team of librarians, information industry professionals and software engineers • simultaneously search both Web pages and a Special Collection database (25 mil documents) • organizes results into folders of related info • plain english queries and complex Boolean expressions • Search Alert Service

  11. YAHOO! • Created at Stanford in 1994 by David Filo and Jerry Yang; first attempt in organizing and classifying the info available on the Internet • searching both Yahoo directory and Google database • general info

  12. Other General-Purpose Search Engines • AOL Search • Excite • MSN Search • Netscape Search

  13. Metasearch Sites • Uses software that searches the search engines; runs your query on several different search engines simultaneously • MetaCrawler: -eliminates duplicates -ranks by relevancy • Dogpile -easy to use interface -can search Usenet

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