The Web can be an incredible resource providing information on nearly any topic
imaginable. Are you planning a trip? Writing an Economics paper? Looking for a movie review?
Trying to locate a long-lost friend? Information sources related to these questions, and much,
much more are available on the Web.
With over two billion pages and more being added daily, the Web is a massive collection of
interrelated pages. With so much available information, locating the precise information you
need can be difficult. Fortunately, a number of organizations called search services or search
providers can help you locate the information you need. They maintain huge databases relating to
information provided on the Web and the Internet. The information stored at these databases
includes addresses, content descriptions or classifications, and keywords appearing on Web pages
and other Internet informational resources. Special programs called agents, spiders, or bots

continually look for new information and update the search services databases. Additionally,
search services provide special programs called search engines that you can use to locate specific
information of the Web.
[1]Search engines are specialized programs that assist you in locating information on the Web
and the Internet. To find information, you go to the search service's Web site and use their search
engine. Yahoo’s search engine, like most others, provides two different search approaches.
Keyword Search
In a keyword search, you enter a keyword or phrase reflecting the information you want.
The search engine compares your entry against its database and returns a list of hits or sites that
contain the keywords. Each hit includes a hyperlink to the referenced Web page (or other
resource) along with a brief discussion of the information contained at that location. Many
searches result in a large number of hits. For example, if you were to enter the keyword travel,
you would get over a thousand hits. [2]Search engines order the hits according to those sites that
most likely contain the information requested and present the list to you in that order, usually in
groups of ten.
Directory Search
Most search engines also provide a directory or list of categories or topics such as Arts
&Humanities, Business & Economics, Computers & Internet. In a directory search, also known
as index search. You select a category that fits the information that you want. Another list of
subtopics relates to the topic you selected appears. You select the subtopic that best relates to
your topic and another subtopic list appears. You continue to narrow your search in this manner
until a list of Web sites appears. This list corresponds to the hit list previously discussed.
As a general rule, if you are searching for general information, use the directory search
approach. For example, to find general information about music, use a directory search beginning
with the category Arts &Humanities. If you are searching for specific information, use the key
word approach. For example, if you were looking for a specific MP3 file, use a key word search
entering the album title and/or the artist’s name in the text selection box.
A recent study by the NEC Research Institute found that any one search engine includes
only a fraction of the informational sources on the Web. Therefore, it is highly recommended that
you use more than one search engine when researching important topics. Or, you could use a
special type of search engine called a metasearch engine."
One way to research a topic is to visit the Web site for several individual search engines. At
each site, enter the search instructions, wait for the hits to appear, review the list, and visit
selected sites. This process can be quite time-consuming and duplicate responses from different
search engines are inevitable. Metasearch engines offer an alternative.
Metasearch engines are programs that automatically submit your search request to several

search engines simultaneously. The metasearch engine receives the results, eliminates duplicates,
orders the hits, and then provides the edited list to you. There are several metasearch sites
available on the Web. One of the best known is Metacrawler.

Specialized search engines focus on subject-specific Web sites. Specialized sites can
potentially save you time by narrowing your search. For example, let's say you are researching a
paper about the fashion industry. You could begin with a general search engine like Yahoo! Or,
you could go to a search engine that specialized specifically in fashion.

1, incredible  [in'kredəbl]
a. 难以置信的
2, massive  ['mæsiv]
a. 巨大的