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Search Engines
Using Search Engines
There are different kind of search engines, and they can work differently, but
there are things they all have in common. It's the commonality that we're most interested
in, so we can easily use these powerful tools effectively.
Search engines are web pages that allow us to looks for information on the Internet.
Some of them, such as AltaVista, use computer programs to find web pages and then
create automated indexes. We use their search engines to search the index the programs
created. Other search engines, such as Yahoo, use humans to make directories of web
pages. We use their search engines to search the directory. Finally some search engines,
like Infoseek, use a combination of those two methods.
In this workshop we're going to explore six of the most popular search engines and
methods that will allow us to use them all in the same ways.
Math and Boolean
Experts would have us believe that the whole trick to using search engines
successfully is in knowing how to construct the "phrase" we type for the
search engine to look for. How we construct this search phrase depends on math and
this weird math science called "boolean". In a nutshell remember that computers
do everything based on math. They don't think, reason, or intuit, like us humans.
Or
When you type in a phrase for the search engine to find, most of them assume that
as long as it finds one (or more) of the words you type, then you are happy. So if
you typed in the phrase:
yosemite camping reservations
Then it would return to you links to web pages that were about yosemite, but also
links to every page about camping (at any place and for camping equipment too) and
also every web page that had anything to do with any kind of reservations (including
reservations for meals at restaurants and Indian lands). This may be way too many
links and it could be very hard to find what you really wanted.
This is called linking all the words with an "or". It's one of those
Boolean connectors and most search engines automatically use it between all
the words you type in your search phrase. So the above phrase, as far as the search
is concerned would be read as "please find me all the web pages containing
the words yosemite OR camping OR reservations".
This may be exactly the way you wanted your search work. But maybe you really wanted
to make sure that you only found web pages specifically about camping reservations
at yosemite national park. Let's see how to do that.
+ (addition sign)
You can use a "+" sign in front of all the words in your search
phrase to tell the search engine "every one of these words MUST appear on the
web pages you're looking for". So we can change our search phrase to:
+yosemite +camping +reservations
Then the search engine will return links to web pages that have those three words
somewhere on the web page. This is a more precise search, as the math folks
like to say. But in addition to web pages with information on making camping reservations
at yosemite you might also get links to camping at many other locations in addition
to yosemite as well as general camping web pages that just happen to mention yosemite
national park.
This might be just the right search method for what you want, but maybe you still
got too many links to look at and want to make your search even more precise.
" " (quotes)
If you want the search engine to look for only the words you type and to find those
words in the exact order and way that you typed them, enclose your search phrase
in quotes:
"yosemite camping reservations"
This is a very precise search. However if what you're looking for doesn't use
that precise phrase on it's web page, then you won't get a match and won't get the
information you want. So you can see that finding information is striking a balance
between finding exactly what you want, without finding too much stuff.
All the search engines we're going to play with use OR and + and " ". Now
we'll look at each of these six search engines and see how they work, how they're
similar, how they're different, and which ones you might prefer to use. Try doing
the same search in each of them, and do that search different ways in each search
engine too. If you're having trouble thinking of search examples you could try some
of the examples listed here.
yosemite camping reservations
windows 98 bugs
nasa mars landings
any current event
makes and models of cars or appliances
travel and reservations to locations of interest
your name
Even More Information
If you would like more information on search engines, how they work and how they
compare to one another, here are two excellent sites for additional exploration:
Search Engine Watch
http://searchenginewatch.com/facts/index.html
Netscouts' Scout Toolkit
http://scout.cs.wisc.edu/toolkit/searching/index.html
Now let's go look at the individual search engines
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