What is Alexa Ranking
The Alexa Ranking is one way to view how popular a site is on the web. However, its quite bias towards sites that have viewers that have the Alexa toolbar.
Some smaller sites may have a higher ranking than bigger sites simply because their content is being viewed by an audience that typically follows the type of crowd that would have Alexa toolbar installed.
An example would be computer marketing websites, tech websites, and the like.
If you want to get a better measure of a websites ranking, google page rank has been a more accurate way to measure a website’s traffic.