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Popular Search
Engines
Information
courtesy of Dowco
The best think
about the World Wide Web is that there are hundreds
of millions of pages online. The worst thing about
it is that there are hundreds of millions of pages
online.
Search engines
work by searching through a previously generated
database of web pages. A query to a search engine
will start a query on the database, with the
results being ordered by algorithms unique to each
search engine.
Google
The search
algorithm is a closely guarded trade secret wqith
all search engines. Since it is important for
businesses to have a high ranking in a search
engine result, webmasters will put in key works or
other tags on a web page to attract a higher search
engine ranking. Algorithms take such obvious tricks
into account to give valid results based on a
page's relevance to a search query, and the page's
general level of importance based on several
factors.
Most databases
are compiled with automated web-bots, small
programs that traverse the internet, copying each
page it comes across. The pages are then cross
referenced with the pages it links to as well as
other pages that link to the first
page.
Databases can
also be put together from human created listings.
However the large size of the internet makes these
search engines less common today.
Yahoo
Yahoo, MSN and
Google are present. In fact according to the
website Alexa, in July 2006 they represent the 3
most visited sites (in that order). Google is
generally regarded as having the largest database
of web pages. so you'll find sites with Google that
you wouldn't find in other search
engines.
One key tag on
web pages that search engines look at which doesn't
show up in browsers is the meta bag. This is a
listing of words in the HTML code that is a
relevant to the page and helps search engines
catalog where that page belongs. On the down site,
these tags can be irrelevant to the page and just
entered to allow the page to show up in searches
for something other that the page subject. If
you've ever searched for movie reviews, and found
the search engine returned links to adult sites,
this is how that was done.
All search
engines allow you to enter advanced searches to
pare down the results from thousands to a more
reasonable number of pages. You can be more
specific in your search parameters, and you can
exclude words, even whole web sites from the
search.
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