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Historical Background An internet server from which hierarchically-organised text files could be retrieved from allover the world. Developed at the University.

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Presentation on theme: "Historical Background An internet server from which hierarchically-organised text files could be retrieved from allover the world. Developed at the University."— Presentation transcript:

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2 Historical Background An internet server from which hierarchically-organised text files could be retrieved from allover the world. Developed at the University of Minnesota, whose sports teams are called “The Golden Gophers” HyperGopher could also display Gif and Jpeg graphic images. Three important Gopher applications were Veronica, Archie and Jughead (named after comic characters!) In use up to 1996 Lost its importance and relevance with the introduction of the first graphical browser, Mosaic

3 Historical Background A Gopher Application software

4 Historical Background Wide Area Information Servers Pronounced : “Ways” Co-existed with the Gopher technology Files had to be stored in a predetermined manner in databases The WAIS user had to connect to known databases in order to retrieve information or files Had the same fate as Gophers – became superfluous with the introduction of browsers and search engines

5 Wide Area Information Servers The primitive XWAIS Historical Background

6 Wide Area Information Servers An improved user interface DatabasesDatabases Historical Background

7 Wide Area Information Servers Historical Background The Windows version

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9 A proper search engine

10 An example of a catalogue Yahoo actually uses Google for its search engine!

11 More of a complete front end for the internet than just a search engine! MSN is another such site

12 A search engine needs to employ a Web Crawler (a sub group of “software agents”) with an unusual degree of autonomy! These are referred to as “Bots” (short for robots), and “Spiders” Spiders or crawlers normally start out with a historical list of links, such as server lists, and lists of the most popular or best sites, and follow the links to these pages to find more links to add to the database.

13 Yes unfortunately this theme enters the realm of Search Engines too! There is a strong rumour that Search Engine companies sell their information about you. Just think – you have recently made a search for hotel quotes and suddenly you start receiving emails advertising hotels and holidays. Is it really a coincidence?

14 …allow the owner of the page to specify key words and concepts under which the page will be indexed. Example: My World Welcome to My World My World Welcome to My World Example: Such an html code would give the following search result: My World Welcome to My World Such an html code would give the following search result: My World Welcome to My WorldExample: Fixing this using Meta Tags: My World Fixing this using Meta Tags: My World Example: The search result this time will be: My World Everything you wanted to know about stamps, from prices to history. The search result this time will be: My World Everything you wanted to know about stamps, from prices to history.

15 And: All the terms joined by “AND” must appear in the pages or documents. Some search engines substitute the operator “+” for the word AND And: All the terms joined by “AND” must appear in the pages or documents. Some search engines substitute the operator “+” for the word AND OR: At least one of the terms joined by “OR” must appear in the pages or documents OR: At least one of the terms joined by “OR” must appear in the pages or documents NOT: The term or terms followed by “NOT” must not appear in the pages or documents. Some search engines substitute the operator “-” for the word NOT NOT: The term or terms followed by “NOT” must not appear in the pages or documents. Some search engines substitute the operator “-” for the word NOT Followed by: One of the terms must be directly followed by the other Followed by: One of the terms must be directly followed by the other

16 Near: One of the terms must be directly followed by the other. Near: One of the terms must be directly followed by the other. Quotation marks: Words between quotation marks are treated as a phrase, and that phrase must be found within the document or file. Quotation marks: Words between quotation marks are treated as a phrase, and that phrase must be found within the document or file.

17 Search engines that return results from a particular website only Usually created by programs that generate a Java Script code One such program is SearchMaker Pro

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19 seaRchmAker[16]=new Array("http://www.geocities.com/powerpoint95forschool/quizcorrect.htm","New Page 1","","Use your browser's Back button please! ");seaRchmAker[17]=new Array("http://www.geocities.com/powerpoint95forschool/quiz3wrong.htm","New Page 1","","Use your browser's Back button please! ");seaRchmAker[18]=new Array("http://www.geocities.com/powerpoint95forschool/shotGallery.htm","ScreenShot s","","Move your mouse to the left-hand side of the screen to access your menu. ");seaRchmAker[19]=new Array……………… <!-- // Script generated by Search Maker Pro: seaRchmAker=new Array();seaRchmAker[1]=new Array………………

20 Webmaster utility sites like Bravenet.com and Cgispy.com offer their services to create a site search engine…for free.

21 If you know of a specialized search engine such as SearchNetworking that matches your subject (for example, Networking), you'll save time by using that search engine. If there isn't a specialized search engine, try Yahoo. Sometimes you'll find a matching subject category or two and that's all you'll need. If Yahoo doesn't turn up anything, try AltaVista, Google, Hotbot, Lycos, and perhaps other search engines for their results. Depending on how important the search is, you usually don't need to go below the first 20 entries on each. For efficiency, consider using a ferret that will use a number of search engines simultaneously for you. A good ferret program is Copernic 2001 downloadable from http://www.copernic.com

22 Another similar ferret software is WebFerret by ZDNet – downloadable for free.

23 If you feel it's necessary, also search the Usenet newsgroups. As you continue to search, keep rethinking your search arguments. What new approaches could you use? What are some related subjects to search for that might lead you to the one you really want? If you feel it's necessary, also search the Usenet newsgroups. As you continue to search, keep rethinking your search arguments. What new approaches could you use? What are some related subjects to search for that might lead you to the one you really want? At this point, if you haven't found what you need, consider using the subject directory approach to searching. Look at Yahoo or someone else's structured organization of subject categories and see if you can narrow down a category your term or phrase is likely to be in. If nothing else, this may give you ideas for new search phrases.

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25 Hell-bent in indexing anything and everything! Over 30 million pages indexed! (until July 96) http://www.altavista.com

26 Claims to have indexed even more pages than Alta Vista http://www.excite.com

27 Indexes the full text of less than a million pages (until May 96), but stores more URL’s http://www.opentext.com

28 Claims that it can grow with the web and index it entirely no matter how big! http://www.hotbot.com

29 Uses multiple spiders – up to 4 at a time! At peak performance the system could crawl over 100 pages per second generating around 600 kilobytes of data per second! http://www.google.com

30 It is simply an online game using Google! The contestant types two words in Google and hopes to receive ONE result only. When this happens it is called a Pure Whack. The contestant can then submit it to www.googlewhack.com where it will be posted. www.googlewhack.com One such Pure Whack is the result of the search for “ambidextrous scallywags”! http://www.googlewhack.com

31 Which used to be available at the following address: http://wwww.cs.colorado.edu/home/mcbryan/WWWW.html For more information go to the following URL: http://www.inf.utfsm.cl/~vparada/html/wwww.html#instr Which used to be available at the following address: http://wwww.cs.colorado.edu/home/mcbryan/WWWW.html For more information go to the following URL: http://www.inf.utfsm.cl/~vparada/html/wwww.html#instr

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33 A Search Engine proper is a database and the tools to generate that database and search it.

34 A Catalogue is an organisational method and a related database, plus tools for generating it.


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