Info by www.about-the-web.com.

Search Engines vs. Directories

Search engines, such as AltaVista, create their listings automatically. Search engines crawl through the web. Search engines eventually find your site and index the pages they find. Page titles, body text, META tags (provided by www.about-the-web.com) and other elements all play a role in what gets indexed. People then search the index of what was found. A complete dictionary of terms can be found at NetLingo the Internet Dictionary :^) on http://www.netlingo.com.  Or access it directly using the following links as-on NetLingo:
The Online Dictionary - start here!
The Pocket Dictionary
The Smileys Page ~:-)
Chat Acronyms & Shorthand!
ASCII Art, ooh la la
All About E-mail
International Country Codes
The Web Design Coloring Book
Color Swatch Reference Guide
HTML Code Cheat Sheet
The Interactive IQ Test
 

A directory such as Yahoo depends on human editors to create its listings. You submit a description of your site to the directory for editors to review. A good site, with good content, will be more likely to get reviewed than a poor site. A search of Yahoo looks for matches only in the editors descriptions.

Some search engines use a hybrid of a crawler and an associated directory. Being included in a search engine's directory is a combination of luck and quality. Submitting your site for review is no guarantee that it will be included in the directory. Reviewers have the final say in who is included in their directory. They often search the Internet on their own looking for good sites to add to the directory.

Search Engine Elements

The three major elements or a search engines are: the spider, also called the crawler; the index or catalog; and the search engine which displays the results of your query in your browser.

The spider visits your web page, indexes it, and then follows links to other pages within the site. This is sometimes referred to as being "spidered" or "crawled." The spider returns to the site every month or two, to look for changes.

The index is a giant database that contains a copy of every web page that the spider finds. When a web page is changed, then this database is updated with the new information.

Sometimes it takes a while for pages or changes to be added to the index. Therefore, a web page may have been "spidered" but not yet "indexed." Until it is added to the index, it is not available to searches by the search engine.

Search engine software sifts through the millions of pages recorded in the index to find matches to a query and ranks them in the order of what it believes is most relevant. Different search engines often produces different results.

Search Engine Tips

If you have a general subject in mind (like "coins"), type the word or words in the Search box and click the Search button. Results are usually listed in order of relevancy based on keywords and other factors.

Advanced Search Features

If you know exactly what you want, you can get better results by entering very specific information into the Search box. Despite differences in each search engine's tools, there are tools that many search engines have in common.

Searching for an Exact Phrase

To require that an entire phrase be found in a search,enter quotes (" ") around the terms. For example, "giants baseball" returns listings where the words "giants" and "baseball" appear together and in that order, either in the title, the URL of the Web site, the description, the keywords, or the document. If no sites are found that contain both terms, sites that contain either term will be displayed.

 

Searching For Required Words

You can type the plus sign (+) or the word AND before a word to require that it be found in all of the search results. For example, giants +baseball (include a space between the first word and the + symbol) or giants AND baseball returns all listings that contain "baseball" and "giants" but not necessarily together.

 

Searching For Excluded Words

Use the minus sign (-) before a word or the word NOT to require that it not be found in the search results. For example, giants -baseball (include a space between the first word and the - symbol) or giants NOT baseball lists sites containing "giants" but not "baseball." Some engines like AND NOT (two words) or ANDNOT (one word) better than just NOT.

 

Searching For Multiple Words

Use the word OR to require that one or the other term be found in the search results. For example, giants OR baseball (include a space on each side of the OR) lists sites containing "giants" or "baseball." You can combine AND, OR, AND NOT by using parentheses. For example, to find documents that contain the word giants but not either the word baseball or football type giants NOT (baseball OR football). You could also type this giants -(baseball OR football). Note: You cannot begin a search with a "-" term. You must put some other search term first.

 

Using Wildcards

You can use the asterisk (*) character to indicate a wildcard search. This is useful when you are trying to match a term that may or may not be plural or might use one of several verb tenses. For example chemi* will find results containing words that begin with 'chemi' (e.g. chemical, chemistry, chemist). You must have at least four non-wildcard characters in a word before you introduce a wildcard. This is not necessary for plurals because a search on cat will also return results containing the word cats, and a search on cats will return results containing the word cat.

Some search engines support two wildcards. The asterisk (*) is used to replace multiple characters and the percent (%) symbol is used to replace only one character. For example psych*ist will find all results which contain words that begin and end with 'psych' and 'ist' (e.g. psychologist, psychiatrist), and gene%logy will return sites containing words beginning with 'gene' and ending with 'logy,' separated by a single letter (e.g. genealogy and geneology) which is useful for commonly misspelled words. You can also use multiple wildcards within a single word.

Major Search Engines