Alexa is a very powerful tool to rank a web site traffic. It ranks the sites using the tracking information from the users having the "Alexa Toolbar" from Internet explorer, Netscape and Mozilla browsers. The major criteria for ranking the site is the combined measure of REACH and PAGEVIEW. The number of unique Alexa users visiting the site grant for the REACH number to raise. PAGEVIEW is the number of Alexa users requesting the URL of the site. However, multiple requests for the same site by the same user is taken as only a single request. Alexa rank is given only the top domain of a site (domain.com) and not for the sub pages of the site.
Alexa ranking is very important for any site, the lower the number, higher is the rank !!!
Here is the link to add the Alexa page rank to your site..
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