Table of Contents
Site MapSearching for Web Pages and Web Sites
While most of the web search engines do not offer all the features that
database interfaces offer in shaping retrieval and precision, many have features that can
eliminate spurious items.
One major difference between searching the web and databases is that many
major databases are indexed for controlled language searching, as opposed to the more
common natural language searching. Natural language terms are ordinary terms in common
usage. Controlled language terms are specifically selected to represent concepts, and are
a further step in organizing the content of databases to enhance precision of retrieval.
Retrieval refers to the number of items or "hits" that the search produces;
precision refers to the number of items within the retrieval that are relevant to the
searcher. Searches for specific words, phrases, or names are generally the easiest type to
perform, and result in low retrieval with high precision.
Subject searching is much more difficult, and generally results in higher
retrieval (especially by web search engines!) with less precision (i.e., more irrelevant
"hits"). The best general advice for online searching is to learn one or two
search engines well, back them up with the meta engines, and practice! For help in
selecting the proper search tool for your needs, refer to Debbie Abilock's excellent summary
on WWW search engines. Before attempting any searches,
make sure that you understand the major search concepts discussed below.
We will discuss in general the kinds of searches that can be performed on the WWW via
the browser interface. WWW hierarchical subject directories (e.g. Yahoo!), WWW search
engines (e.g. Alta Vista) or WWW meta search engines (e.g. MetaCrawler) can be used to
locate either pages in websites containing relevant information, or used to locate
databases accessible via the WWW which can be searched further. Many WWW databases have
interfaces designed to facilitate searching from the web browser. Many large websites use
their own search engine at the site to locate content within the web site. These generally
are simple search engines that search for user-supplied keywords.
To view the demo movies for the browser tips, click on the
hyperlink; then view the demo. When motion stops in the screen, close the RealPlayer
window to return to this page.
Page text search
(Demo)
- Use the Find or Find Again command (generally in the Edit menu of your browser) to
locate specific text strings on large web pages.
Graphics no load
(Demo)
- To speed up page loading, turn off graphics loading in the browser Preferences or
Options menu. To look at specific graphics, click on them. This is useful for modem
connections.
Save (Demo)
- Rather than read long passages of text online, save the page to a file and peruse it
without the constraints of modem line fees.
View command
(dates) (Demo)
- This can be used to find out Info, which tells when the page was created and last
updated. This helps in determining the currency of the information it contains (see
evaluation section). The View command also allows you to view the HTML source code for the
page, an aid to learning to create your own HTML documents.
-
- Print (Demo)
-
- Like the save page command, a page can be sent to the printer and viewed offline to
minimize connect charges.
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- Copy and paste
(Demo)
-
- Text or charts cited in your authored works can be copied and pasted to your pages. It
is absolutely important to correctly cite them to credit the original author and avoid
plagiarism (see citing online sources). Also, URLs can be copied from text and
pasted in the browser location window.
-
- Incremental
truncation of the URL (Demo)
-
- If the location that you seek cannot be accessed, start deleting elements of the
directory path (between the slashes "/") in the browser location box
sequentially from the right end towards the left.
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- Go choice on
the menubar (Demo)
-
- Clicking on this menubar item displays a drop-down menu of the most recently visited
websites accessed during your current browser session; this can be used to directly access
sites you have visited instead of using the arrow buttons to move forward or backward
sequentially through the pages.
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- History choice in
Netscape Communicator (Demo)
-
- This item can be found by clicking the Communicator item in the menubar; it offers a
more extensive list of websites that you have visited, stretching back several days.
- Basic interface
- The simple search interface is generally a text box where you can type search terms
without specifying relationships or using search syntax. The retrieval from these searches
is generally quite large, and the precision is generally low..
- Advanced interface
- The advanced interface offers the opportunity for introducing relationships between
terms with search syntax, and for limiting the output of the search. This produces
smaller, more specific sets with less irrelevancy (lower retrieval and higher precision).
Meta search engines combine several web search engines to conduct wider searches very
quickly. Because each component search engine may have its intrinsic search syntax and
logic, usually only very broad and general subject searches can be performed. Meta engines
are very useful in searching for a specific word, name, or phrase.
WWW Directories & Lists:
These tools attempt to simplify searching by identifying subject headings and arranging
them in hierarchies for searchers. They are often a good place to start when one doesn't
have the necessary background to specify search terms or synonyms. They may also
incorporate a simple search interface to get the searcher to the most specific page within
a topic heading (e.g. Yahoo!). Others may be simply lists of lists of hyperlinks that are
dedicated to a specific subject(s).
Specific Directories:
These can be searched for phone numbers, email addresses, maps, software, etc.
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