If you can get enough websites to link to yours it can help you greatly with what's known as "link popularity," which is one of the criteria used by most of the major search engines when ranking websites. Theoretically, the better your popularity,the higher you rank.

A growing number of search engines use link popularity in their ranking algorithms. Google uses it as its most important factor in ranking sites. HotBot, AltaVista, MSN, Northern Light, Inktomi, Excite and others also use link popularity in their formulas. Eventually every major engine will use link popularity, so developing and maintaining it are essential to your search engine placement.

Link popularity can do a lot for your site. Not only will many search engines rank you higher, but links from other sites will also drive more traffic to you.

Link popularity is much more than a measure of how many links point to a site. Search engines use far more sophisticated formulas to gauge how popular sites are. In general, however, link popularity is measured by the following three factors:

Number of Links - The more, the better. Although lots of irrelevant links are less effective than a few relevant ones, they're better than nothing. Inktomi, a company that provides search results to engines like HotBot, still values the number of links more than anything else.

Relevance - Search engines prioritize incoming links from pages that are relevant to the page in question. For example, if you sell puppy food, a link from a dog food supplier can boost your rankings more than one from, say, your sister's gardening site.

Link text - The text used to describe a link can also affect your rankings. These three links all point to the same URL but use different text:

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