Link popularity and search engines
Hyperlinks are the number 1 factor determining your ranking in search engine results. The effect of links can be seen in a phenomenon known as Googlebombing.
Search Google for "miserable failure", and the first result is the biography of George W Bush. This is how it's done. Many people have linked to his biography like this: miserable failure
The importance of link text (anchor text)
The interesting thing about the example is that the words "miserable failure" don't appear in the biography at all. They only appear in the text of links to the page. The text in links is very important in defining to Google what a page is about.
Link text is normally the result of human editing. That makes it very useful to search engines.
If I were to link to another page on the web I would decide what is is about the page that is relevant to my visitors, and include a very short summary within the link. I am essentially summarizing that page based on my impressions, and search engines are more than happy to make use of my work.
You could base a search engine on links and link text alone. Any site with 500 inbound links (backlinks) with the words "computer parts" is bound to be more useful and relevant for the search terms "computer parts" than a site with 100 inbound links including those terms. However, a site with 100 inbound links including the words "beach holiday" will clearly be more relevant for beach holidays than the page with "computer parts" in the links.
The same is true for links between pages on the same site as well as links from one site to another. Cast your eyes over our navigation menu to see how this works.
Page rank and page importance
Supposing the W3C (the "governing body" of the web) were kind enough to link to this web site. They are important and serious people, and would have to consider the information on this site extremely useful if they were to bother linking to us.
Google realize this - they know how important the W3C is by the number of links to their site, and would weight the opinion of the W3C extremely highly. Google would increase the ranking of this site accordingly.
They do this by a system called "pagerank". Pagerank is a measure of the importance of a page depending on the number and quality of inbound links, and is displayed on a scale of 0 to 10.
The W3C has a page rank of 9 on a page (an extremely important page). They find that our site covers all of the additional information their visitors could wish for, so their page contains a single link to our site. This could result in our site achieving a page rank of 8.
If the W3C linked to us on a page with 100 other links. They are saying they couldn't find a single page with relevant information so they offer their visitors 100 pages to look at. Our page would clearly be considered less useful in this situation and might achieve a page rank of 6 or 7.
It is possible to view the page rank of your pages by downloading the Google toolbar.
How to increase inbound links
Very successful sites on the internet tend to get where they are because they provide useful information and people like to link to them.
Unfortunately there is a "Catch 22" situation. Without the first few links you won't be noticed by search engines, and people who would otherwise find your site useful and link to you won't be able to find your site at all.
You need to start the process off by pursuing inbound links. This can be done in a number of ways (listed below), but always remember how important quality is to Google. Make sure your link adds usefulness to the site that is linking to you. Avoid putting your link on poor quality or spam sites - these links could reduce your reputation. These are a number of quality sources for your links:
Directories
There are a number of free, quality directories where you can submit your site. Links in directories are very useful to visitors to directories. You can find directories by searching Google. If your site is about computers then search for "computer directory". Add your link if you think it is a quality directory.
Link Exchange
It is OK to exchange links. If you happen to find a site where your link would add to that site's content then link to that site and e-mail them explaining what your site is about and ask if they might consider linking back to you.
Avoid any automated link exchange programs and avoid linking to poor quality or spammy sites. Search engines can penalize your site if you link to penalized sites.
Links embedded in JavaScript or redirecting off the linking site cannot be followed by robots. The best way to see if a link can be followed is to follow another link from the same page to another site, then type in "linkdomain:" then the address of page on the other site into Yahoo. If the other site is visible in the results then the link can be followed by robots.
In summary
Try to get as many quality inbound links to your site as possible with your keywords in the link text. This will increase your ranking for those keywords, and to will also increase your rankings for other keywords.
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