The "Sites Linking In" count shows the number of sites that Alexa found that link to this site.For more information please see this explanation of how Alexa determines the number of sites linking in.
The load time of an individual page is how long it takes for the DOM - the structure of the page - to be loaded.
Bounce Rate (%) Percentage of visits to the site that consist of a single pageview.
Daily Pageviews per Visitor Estimated daily unique pageviews per visitor on the site.
Note that this list is not the same as referrals from upstream sites.
There is not necessarily a link between the upstream site and this site.