| |

NOVA
Libraries Research Guides | Alexandria
Research Guides |
Subject
directories are
created by people,
and provide a collection
of links to Internet
sites organized
into subject categories. They
are usually more selective than search engines. Subject
directories usually
provide a search
engine to query
their holdings.
Search
engines are computer-generated
searchable databases of Internet resources. They usually log
each word on each web page, so when a search engine is queried,
it will search for your terms on each page in its collection.
Search
engine disclaimers:
Search
engines do not index all Web pages.
-
Database
content will not show up in a search engine
result. This includes magazine and newspaper databases
available through the library home page, such as Expanded
Academic. These resources have been called the
"Invisible Web" since the information in these databases
cannot be "seen" by search engines. If you need magazine,
journal, or newspaper articles, the best place to
start looking is usually in an online
database, NOT A SEARCH ENGINE.
Use
a subject directory:
· When
you have a broad topic.
· When
you want to see a list of sites recommended
and reviewed by experts.
· When
you want a list of sites, not pages within
a site, on your topic.
·When
you want to avoid getting pages that only
mention your term once or twice.
Use
a search engine:
· When
you have a narrow topic, or a topic with
obscure terms.
· When
you need to be comprehensive and want
to search the entire text of all pages
accessible
through
the search engine.
· When
you want as many results as possible
on your topic.
· When
you are searching for a specific site.
· When
you want to search for images, sounds,
or file extensions.
- Pick
good search terms.You can enhance
your chances of finding relevant sites if
you:
- Know
what you're looking for - for example, instead
of something on gun control, try "gun
control" teenagers schools.
- Avoid
being too general (e.g., instead
of cats, try Norwegian forest cat).
- .Or
too specific (e.g., instead of red
flashing erupting volcanoes as clip art,
try volcanoes and gif).
- Increase
precision by using AND (or the +
sign, depending upon the search engine) and
quotation marks in appropriate situations:"star
wars" and film
- Use
online Help to determine search protocols
and to get more search advice specific
to each engine and directory.
- Use
more than one search engine or subject directory. Engines
and Directories vary in coverage. Yahoo!,
for example, tends to be a more "commercial" subject
directory, while Librarian's Index
to the Internet tends to be more academic
in nature. Google is a very large
search engine and quite accurate, but AltaVista can
be very good for general use. AskJeeves frequently
provides good, interesting results. These
search engines do not cover all parts
of the Web, so if the first search
engine you
try doesn't get you what you need,
try another.
- Evaluate
what you find. Anyone
with a computer, modem, and Internet
connection can put anything on the
Web. There are no "Internet
Police." Look for bias, credibility, accuracy,
and date of last update. See the Library's "How
to Evaluate Web Information" link for
more details.
- Use
NOVA Library's Best
of the Web (available off of the Internet page)
for good, interesting, and useful Web sites, both practical
and academic in nature.
For
more information on search engines and subject
directories try these sites:
Search
Engine Showdown: www.searchengineshowdown.com
Search
Engine Watch: searchenginewatch.com
Copyright
Northern Virginia Community College. Created by Anne
Anderson and Beth Weixler. Last updated Oct. 2006.
|