When you want to find something on the Web there is a range of search engines and directories that are available for you to use.

However just visiting a search engine and entering in the name of what you want to find is not enough.  To get the best results out of search engines you need to understand how they rank and retrieve pages.


How Search Engines Rank Pages
 
Keywords

To determine the relevancy of a web site to your query search
engines follow a set of rules that mainly have to do with the
location and frequency of keywords on a web page.  Search Engines
look for your keywords in the following way:

  Keyword in the Title - pages with your entered keywords appearing
    in the title are assumed to be more relevant that others to the topic.
  Keyword in top of Web page do your keywords appear near the
    top of a web page, such as in the headline or in the first few
    paragraphs of text?
  Frequency a search engine will analyse how often keywords appear
    in relation to other words in a web page.  Those with a higher frequency
    are assumed by the search engine to be more relevant to your needs
    than other web pages, and are therefore ranked more highly in the return
    search results.

All major search engines follow this location/frequency method to some degree.  None do it exactly the same, however, which is another reason why the same search on different search engines produces different results.

Meta Tags

These are tags hidden within a pages html code that contain a description of the site, or a list of the sites keywords according to the designer.  The keywords are designed to alert a search engines attention to what keywords our site might be relevant to.  The description is what the designer wants to appear for a searcher in the summary when their search engine has listed their site.


General Hints
 
Upper and/or Lower Case

Most search engines interpret lower case letters as either upper or lower case.  So:

       If you want both upper and lower case occurrences returned, type
         your keywords in all lower case letters.
       If you want to limit your results to initial capital letters or all upper
         case letters, type your keywords that way.

Singular vs Plural

Most search engines interpret singular keywords as singular or plural. 
If you want plural forms only, make your keywords plural.

Truncation

A few search engines support truncation that allows variations in spelling or word forms.  The asterisk (*) symbol tells the search engine to return alternate spellings for a word at the point that the asterisk appears. 

For example: civil* returns web pages with civil, civilise, civility and civilisation

You should not, however, truncate with less than the first four letters of any word.


Searching Using Boolean Logic
 
To use search engines effectively, it is essential to apply techniques that narrow results and push the most relevant pages to the top of the results list. 

Identify Keywords the secret to getting the right result when searching is in choosing the right keywords. 

The easiest way to explain this is to work through the following example:

Aim: to find information on what is happening with Napsters battle with against the Recoding Industry of American Artists (RIAA), the keywords might be:

Napster RIAA  MP3

If you entered these three words together the search engine would return you all pages it found containing any single one of these words.  As a result you would get a huge number of pages back, many of which would be irrelevant.

It is in this situation when an understanding Boolean logic comes in very handy.

There are two types of Boolean logic: full and implied.

Full Boolean Logic uses the words AND, OR and NOT
Implied Boolean Logic uses the symbols + or

A. Boolean AND
In order to make sure our search engine returns only pages that contain all three of those words, we can use implied or full Boolean logic by entering either of the following into the search field:

Implied:  Napster +RIAA +MP3
Full: Napster AND RIAA AND MP3

Result: The search engine will now only return web pages where the words Napster, RIAA and MP3 all appear within the same web page.

B. Boolean NOT
AND NOT tells the search engine to retrieve web pages containing one keyword but not the other.  For example if we wanted to find information on dolphins (the aquatic mammal), but not be bombarded with webpages devoted to Miamis American football team, we could use either implied or full Boolean logic as follows:

Implied:  dolphins Miami
Full: dolphins AND NOT Miami

Result: The search engine will now only retrieve web pages where dolphins, but not Miami, appear.

C. Boolean OR
Linking search terms with OR tells the search engine to retrieve web pages containing any, some or all keywords.  We could use either implied or full Boolean logic as follows:

Implied: using two or more words with nothing surrounding or separating them is equivalent to OR.
Full: Parrots OR Budgerigars OR Cockatiels

Result: The search engine will return pages with a single keyword, several keywords or all keywords. 

Sites that support Boolean Logic are:
www.altavista.com
www.google.com
www.excite.com
www.go.com


Phrase Searching
 
Surrounding a group of words with double quotes tells the search engine to only retrieve documents in which those words appear side-by-side.  Phrase searching is a powerful search technique for significantly narrowing your search results, and it should be used as often as possible.

Example:  John F. Kennedy New Zealand global warming

You can even combine phrase searching with implied and full Boolean searches.

Implied: +heart disease +cause
Full:  heart disease AND cause


Title Searching
 
This is one of the most effective techniques for narrowing results and getting the most relevant websites listed at the top of the results page.  A web page is composed of a number of fields, such as title, domain, host, URL and link.  Searching effectiveness increases as you combine field searches with phrase searches and Boolean logic.

For example: if you wanted to find information about George Washington and his wife Martha, you could try the following search:

Implied: +title:George Washington +President + Martha
Full: title:George Washington AND President AND Martha

The above title search example instructs the search engine to return web pages where the phrase George Washington appears in the title and the words President and Martha appear somewhere on the page.  As with plus and minus, there is no space between the colon (:) and the keyword.


Domain Search
 
The Domain Search allows you to limit results to certain domains such as websites from the United Kingdom (.uk), New Zealand (.nz), educational institutions (.edu), or military sites (.mil) and so forth.

Implied: +domain:uk +title:Queen Elizabeth
Full: domain:uk AND title:Queen Elizabeth

Implied: +domain:edu +lung cancer +smok*
Full: domain:edu AND lunch cancer AND smok*

URL Searching the URL Search limits search results to web pages where the keyword appears in the URL or website address.  A URL: search can narrow very broad results to web pages devoted to the keyword topic.

Implied: +url:Halloween +stories
Full: url:halloween AND stories