Subject Directories
Subject directories
provide lists of Web sites that have been organized by human beings.
If your topic is included, you can often find good starting points by
using a subject directory. Subject directories usually offer you
two search approaches -- you can select a general topical area, and then
narrow down; or, you can begin with a keyword search. Subject directories
cover only a small fraction of all Internet resources. Examples: Yahoo!
is best known overall; commercial sites comprise about 75% of its database.
Librarians' Index to the Internet lists high quality Web resources,
selected by librarians..
Search Engines
Humans organize and
catalog subject directories. Current estimates are that there are
about 9 million new Internet resources per day. Subject directories
can cover only a small portion of what's available. Search engines, by
contrast, use computer programs called spiders or robots to crawl the
Web and bring back information about publicly accessible resources. When
you use a search engine, you type keywords into a search box.
The search engine searches its database and gives you back a results list
that has links to Internet resources that have the terms. To retrieve
results focused on your topic, you must formulate your search statement
in ways required by the specific search engine you are using. Google
is the largest and most popular search engine.
Meta-Search Tools
There are a number
of tools that broadcast a search to more than one search engine.
It is important to note, however, that although meta-searching has the
advantage of simplifying queries, you are not able to take full advantage
of specific search options offered by each specific search engine. It
is best to use a meta-search engine when you have a very specific or unusual
search term to gauge the extent of Web resources. Examples: Dogpile;
Profusion.
Summary
| Subject
directories |
Made by
humans; cover only part of the Internet |
Use in initial
searching or when you want general information. |
| Search
engines |
Made by
computer programs; cover large portions of the Internet |
Use for
specific, focused searching. |
| Meta-search
tools |
Broadcast
search to a number of search engines; search precision is sacrificed.
|
Use if you
have a very specific or unusual search term, or just to gauge
what's out there. |
To get to the library's list of search engines, meta-search tools, and
subject directories:
- Go to the Cabrillo
College Library homepage <http://libwww.cabrillo.cc.ca.us>
- Click on Search
the Internet
T.
N. Smalley 7/99; last rev. 8/05 |