Internet Marketing Glossary

Definition: PageRank

PageRank is a system for ranking web pages by popularity that was originally developed by Google's founders. PageRank is also a number, commonly expressed as an integer between 0 and 10, assigned to each web page as a measure of that web page's relative importance amongst all pages on the entire web. A page's PageRank can also be expressed as the probability that a Web user who does nothing but click on random links will arrive at that particular page.

The basic idea behind PageRank is to measure the popularity of a web page — a link from a web page is considered to be a "vote" for the page receiving the link. The more incoming links, the higher the PageRank for a specific web page. Links from pages with high PageRank are far more valuable than links from pages with lower PageRank. The PageRank value that a page passes to its linked pages is calculated by dividing that page's PageRank by the number of outbound links on the page. A link from a page that has five outbound links is able to pass on ten times as much PageRank as a page that has 50 other outbound links. The PageRank scale is logarithmic, so a PageRank of 7 is actually a much higher value than a PageRank of 6.

PageRank as it was originally conceived has long been considered obsolete by Google and other search engines because of its susceptibility to manipulation. This is not to say that it is now completely meaningless, as it is used as an element in the calculation of TrustRank, the algorithm that has become more important. Many SEOs still think exclusively in terms of PageRank, however, which leads them to suggest or implement risky linking strategies that are likely to harm your website's search engine rankings.

If you are shopping for help in increasing your website's search engine rankings, a warning sign of incompetence is an over-reliance on PageRank as a metric. Beware the SEO company that offers to get you thousands of links to increase your PageRank, or judges the value of incoming links based primarily on PageRank. They probably don't know what they are doing.

If you want to learn more about the mathematics behind PageRank, here's a nice analysis of different methods of calculating PageRank.

Here's what Google itself has to say about PageRank.

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