Once your pages are added to a search engine's index, people can do a search in that search engine using various keywords to find pages that best match their search criteria. These matches will be ranked or positioned in order of importance. Therefore, appearing within the first few pages of the search engine listings is of most importance since searchers don't spend a lot of time scrolling through dozens of page listings to find what they are looking for. The exact rules that the search engines and indexes use to rank pages for relevance are generally tough to ascertain and change often. Here are the basics elements of search engines.

There are three important elements to search engines: the database, the user search, and the ranking of results.

The database is the container of indexed descriptions of web pages. Originally they were a link list. Later they bacame huge link lists with small descriptions for each link. Today they use special search algorithms to find and sort results to provide the searcher the most relevant web pages throuogh the use of keywords and keyword phrases. The average time between submitting a web page to the search engines and getting it into the databases are in the 5-8 weeks range (with each search engine having its own schedule). Search engines also periodically check their databases to see if web pages are still in existance and to see if they have been recently updated.

Search engines give each page they find some measure or ranking of the quality of the match to a search query. This is known as the page's relevancy to the keyword or keyword phrase that was used in the search. Relevant scores reflect the number of times a search term appears, how often it appears in the title, whether it appears at the beginning of the document or at the end, what's its prominance in the HTML tags, and whether or not all the search terms were near each other. Some engines allow the user to control the relevance score by giving different weights to each search word. A search term used too many times within a web page can be considered spamming and search engines will penalize a page for for this by dropping its relevancy in its listings or by banning the page from their database. Generally, you shouldn't overdo the use of a keyword or phrase on a page but you shouldd be sure to use your keywords and keyword phrases to a large extent (not exceeding somewhere in the 15-25 count range),

Each search engine uses different factors in determining relevancy and ranking. For example, some search engines will not list a page highly if there are no links to other files or pages within the page.

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