Search Engines

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					                                       Search Engines

There are differences between asking questions and specifying keywords and there are
differences between search engines (Google) and Indices (Yahoo).

When using a search engine or index, unless I come up with valuable information on the first or
second page of hits, that usually means that I did not do a good job of specifying search terms.
Despite advances in computer programs that can discern keywords in a sentence, just typing in
key words is often the most efficient way to search. This also illustrates the different kinds of
content and the way content is gathered on different kinds of search portals. Searching with
keywords is more an art than a science. As you will learn when you take the cataloging course,
specifying keywords is often not the easiest thing in the works. Becoming good at it takes time
and a lot of trial end error but when you do get good at it, using precise key words to do your
searches makes searching very efficient.

Search Portals - Search Engines, Metasearch Engines, Directories or Indices

There are three major types of search portals - search engines, metasearch engines, and
directories or indices. Each one operates differently so it's important to know how it gathers
information from the web and then how that information is presented.

Search Engines

Search engines use automated programs called spiders to read web pages. These spiders search
the web for web pages, assign keywords to the pages either by content or using the keyword field
on the webpage, and then creates a database of information. When you type in a search request
into a search engine, a program matches your keywords to keywords in the database. Then it lists
the webpages that match. Google is by for the most used search engine with Alta Vista, Lycos,
and others.

There are studies called Overlap Studies that show that a single search engine such as Google
cannot be totally relied upon for web searching. Information from a UC Berkeley Teaching
Workshop on search engines gives a comparison of several search engines and recommendations
about getting second opinions.

(When I first started teaching about search engines, there were 25 or 30 different choices. Now
the list is down to about ten to fifteen. In the last several years, the major search engines have
swallowed up many of the smaller ones. The list below gives the more popular ones.)

    AllTheWeb                             AltaVista                 Excite   
    Gigablast                             Google                    HotBot    
    Lycos                                 MSN                       Wisenut       
     411 Search

You can read more about search engines and directories from a marketing perspective at a
commercial site called SearchEngineWatch.

Metasearch Engines

Metasearch engines are a type of search portal that doesn't maintain their own database or list of
keywords and sites. Instead when you submit a search to a metasearch engine, the metasearch
engine sends the request to many different search engines and directories at the same time. The
results are a list or web sites similar to a search engine or a directory. In theory, the advantage is
that your search is being submitted to several different search engines and directories at the same
time. In other courses I've taught, we've tested this theory. In no way are our results scientific or
rigorous but the general feeling was that good search engines such as Google do as good or
better a job than many metasearch engines. I was quite impressed with a search engine called
Teoma. Unfortuately, it has been subsumed into and doesn't have the interesting
interface anymore.

       Ask Jeeves                The BigHub                Dogpile
       Ixquick                   Metacrawler               Mamma
       ProFusion                       Vivisimo

You can read more about metasearch engines from a marketing perspective at a commercial site
called SearchEngineWatch.

Directories or Indices

On the surface, directories and indices look like search engines because you type in key words
and the site returns a list of sites that match the key words. The difference between them though
is significant. Directories are lists of web sites that are compiled by humans where search
engines use an automated program called a spider to compile a database of web pages. Websites
are listed in a directory either because an editor found the site and listed it or because the
webmaster of the site submitted it to the directory. Directories and indices are also browsable.
They often contain a lists of topics that is hierarchical. By clicking on the topic, you see a list of
subtopics. Continuing to click may give you additional subtopics or web pages. When you do a
search in a directory you are not searching the Internet but just searching the list of sites that the
editors have included in the directory.

             1st SPOT Web Directory         
            Beaucoup                             Galaxy
            Librarians' Index to the Internet    LookSmart
            Open Directory Project               SearchKing

You can read more about search engines and directories from a marketing perspective at a
commercial site called SearchEngineWatch.

Kids Search Portals

        Ask Jeeves for Kids                 Awesome Library    
        Cantufind                           Fact Monster      
        Kids Sites                          KidsClick  !/
        LycosZone                           SurfSafely 
        WGW for Kids                        Yahooligans for Kids

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