AVG forum: about avg DNT

hi guys . this is the comment what i saw about social button topic of AVG's DO NOT TRACK .

Social buttons:

Elements designed for improving the social-networking experience. Social buttons are served from the social networks to the site you are visiting. They can collect data about your online activity while you are logged-in. Examples of Social buttons include: Facebook Social Plugins, Twitter Button, Google +1. Social buttons are allowed by default.

but i cant understand what this means .. but i understood one thing .. i may or may not be wright .. please comment some thing about it if i am correct ..
otherwise tell me the clear definition guys please .

well , what i understood is nothing but
for example :

when we( person X ) comment on others post ( person Y 's post) on facebook , its server tracks information about who commented on the post, how many a times did the person X commented on the person Y's post and all .. and there is some applications in facebook namely " people who commented most on your timeline " .. if person Y use this app it shows that person X is the top most commentor on your post or some thing like this ... this is same in the case of a google +1 button , i hope .. ?? i we block the social buttons then no information about us is transmitted .. am i right .. is my understanding correct ..???