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1 © Netskills Quality Internet Training, University of Newcastle
Search Engines and Other Animals
© Netskills, Quality Internet Training, University of NewcastleNetskills is a trademark of Netskills, University of Newcastle.
Partly funded by the
http://www.netskills.ac.uk/
2 © Netskills Quality Internet Training, University of Newcastle
TopicsThe web as an information sourceTypes of search site:
Search engines Metasearch Engines Classified directories Subject gateways Invisible web Specialised sources
What to use when?
3 © Netskills Quality Internet Training, University of Newcastle
The Web: What's Out There? Online books Electronic journals Bibliographic databases Full-text materials
Personal home pages Discussion groups & mailing lists Audio, video, images Interactive resources Free & subscription services
4 © Netskills Quality Internet Training, University of Newcastle
The Internet As An Information Resource
Advantages Up-to-date Access at point of use Accessible 24 hours a day Access to a wide variety of
information sources
Disadvantages Quality? Lack of organisation Poor search tools? Limited help
5 © Netskills Quality Internet Training, University of Newcastle
Sites for Finding Information On The Web
Search Engines Metasearch Engines Classified Directories Subject Gateways Invisible web Specialised sources
Note: Some sites offer more than one way to search
uk.yahoo.com
www.intute.ac.uk
www.google.co.uk
6 © Netskills Quality Internet Training, University of Newcastle
Search EnginesAutomated indexing of (lots of)
web pagesSearched by keyword Find lots of information Results ranked by relevancyGood for specific queries Too much information?
www.google.co.uk
www.alltheweb.com
7 © Netskills Quality Internet Training, University of Newcastle
Metasearch EnginesEnable you to search across a number of
(commercial) search services simultaneouslyIncreases proportion of web searched Usually remove duplicate resultsMay have limited query language
www.metacrawler.com
www.dogpile.com
8 © Netskills Quality Internet Training, University of Newcastle
Classified DirectoriesHuman-compiled general
subject listing of resourcesCommercial or academicBrowsable and searchableSearches catalogue record -
not web pages themselvesGood for general queriesFind fewer but higher quality
resourcesdir.yahoo.com
www.lii.org
www.bubl.ac.uk
9 © Netskills Quality Internet Training, University of Newcastle
Subject GatewaysA subject-specific
classified directoryContain high quality resources
selected by subject specialistsGood for general queries
Intute (formerly the Resource Discovery Network) www.intute.ac.uk
Subject Gateways collectionwww.hw.ac.uk/libWWW/irn/pinakes/pinakes.html
10 © Netskills Quality Internet Training, University of Newcastle
The 'Invisible' or 'Deep' WebNot accessible by web search
engine spiders Information held in databases Very recent sites Different file types (eg PDF, Word) Information beyond search engines index limit
(eg may only index first 200 words on page)
Use directory sites to find 'invisible' sourcesFind out more:library.albany.edu/internet/deepweb.html
11 © Netskills Quality Internet Training, University of Newcastle
What to use when?Search Engines
If you have a very specific query If you need lots of information
Metasearch Engines If you have a very specific query If you want to increase the proportion of the web searched If you're not worried about creating a very complex search
query
Classified Directories & Subject Gateways If you have a general information need If you want to browse through structured information If you want higher quality information
12 © Netskills Quality Internet Training, University of Newcastle
SummaryThere are a number of
different tools available for searching the web
The tool you choose to use will depend on your information needs
You may need to use more than one tool to find the information you need
13 © Netskills Quality Internet Training, University of Newcastle
Note for Hands-On Session
Try searches used in the workbook then…
Try searches using your own keywords