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4. Feature Article-

How Do Search Engines Work - Web Crawlers
By Ron Richardson - Editor -

It is the search engines that finally bring your website to the notice of the prospective customers. Hence it is better to know how these search engines actually work and how they present information to the customer initiating a search.    

There are basically two types of search engines. The first is by robots called crawlers or spiders.

Search Engines use spiders to index websites. When you submit your website pages to a search engine by completing their required submission page, the search engine spider will index your entire site. A spider is an automated program that is run by the search engine system. Spider visits a web site, read the content on the actual site, the sites Meta tags and also follow the links that the site connects. The spider then returns all that information back to a central depository, where the data is indexed. It will visit each link you have on your website and index those sites as well. Some spiders will only index a certain number of pages on your site, so don't create a site with 500 pages

The spider will periodically return to the sites to check for any information that has changed. The frequency with which this happens is determined by the moderators of the search engine. It is so important to continuously create new, relevant content for your site. Every time you add new content, the spiders will be alerted and crawl your pages more often, giving you a higher ranking in the search engines.

A spider is almost like a book where it contains the table of contents, the actual content and the links and references for all the websites it finds during its search, and it may index up to a million pages a day.

Example  Excite, Lycos, AltaVista and Google.

When you ask a search engine to locate information, it is actually searching through the index which it has created and not actually searching the Web. Different search engines produce different rankings because not every search engine uses the same algorithm to search through the indices.

One of the things that a search engine algorithm scans for is the frequency and location of keywords on a web page, but it can also detect artificial keyword stuffing or spamdexing. Then the algorithms analyze the way that pages link to other pages in the Web. By checking how pages link to each other, an engine can both determine what a page is about, if the keywords of the linked pages are similar to the keywords on the original page.

So don't go keyword stuffing on your site. A good site will have about a 6% keyword density on it. So out of every 100 words on the page, 6 of them will be your main keywords. If you try and stuff to many keywords thinking you'll get higher rankings...think again. Not only will your content be deemed 'spamdexing', but it will tend not to make much sense to your readers.