Top Keywords from Search Engines The table shows the top keywords that sent traffic to this site from major search engines over the past 6 months. Upstream Sites Upstream sites are sites that people visited just before they visited this site.
Note that this list is not the same as referrals from upstream sites.
We identify these patterns by looking at the activity of millions of web users throughout the world, and using data normalization to correct for any biases.
The more traffic a site gets, the more data we have to calculate estimated metrics.
For more information please see this explanation of how Alexa determines the number of sites linking in.