On the right-hand side of each item, you will see a with a number. This number represents the total number of positive interations between our users and a particular item. Some positive interactions we track include clicks, shares, and likes.
We use Activity in a number of ways to show our users better content. Top Authors and Trending as well as various other lists and rankings are calculated with activity scores.
Activity also largely deetermines which item we share on Twitter, Facebook, Tumblr and other social profiles.