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 Using e-mail Finding information SearchstrategiesSearch enginesInformationgatewaysSpecificsearchingEvaluating information      |
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Finding Information Search engines and directories
Terminology The terminology used to describe Internet search tools is not straightforward. Different terms may be used to describe the same tool - or the same term used to describe different ones. Thus, while the following classifications are widely used, you may come across the terms used slightly differently on other sites. In addition, search tools are increasingly hybridized, offering combinations of - for example - search engines and directories. Search engines A search engine is a programme which indexes web pages automatically. Search engines use "spiders" or "robots" to index web pages and add the results to the search engine's database. When users enter a query, the query terms are compared with the index and matching results displayed. Search engines do not rely on human intervention to build up their indices, with the "spiders" adding to the index around the clock. The advantage of this is that search engines can build up very large databases; the disadvantage is that only a small percentage of this information may be relevant to what you are looking for. AltaVista is an example of a search engine. Directories Unlike search engines, directories (although they are often searchable) are compiled manually. Information about web sites is entered manually, and each web site included in the directory will be slotted into an appropriate category such as "travel" "food" or "education". Yahoo is an example of a directory. Metasearch engines Individual search engines have different strengths and weaknesses, and you will not get identical results from a query submitted to - for example - AltaVista and Excite. Metasearch engines are search engines which submit your query to a number of search engines simultaneously. Major search engines and directories Among the major search engines and directories are:
Metasearchers are a special form of search engine which conduct a search simultaneously on several search engines. Among the top metasearchers are:
A list of South African search engines is maintained on the ANC web site at http://www.anc.org.za/search.html. Included are:
The Daily Mail & Guardian offers an overview of South African
search engines, with brief explanations of how they work. While the article dates back to April 1998,
it still offers some useful tips: See the relevant section on the Yenza! page on finding specific types of information. Links to other search engine resources
The University of California at Berkeley offers an
excellent online tutorial on finding information on the Internet, covering from basic to
advanced search techniques. Included are an overview of the features of major search
engines, and detailed instructions for using seven of the most commonly used search
engines: Search Engine Watch
offers a wide variety of
resources relating to search engine, including articles, reports, tutorials, links to
other resources and information on designing search engines:
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