As far we know Google impacts negative results, when we get and sell Paid links. Google recommends to use nofollow tag on paid links.Eg: I give link to one of my partner website on Footer or Side navigation of my website, without nofollow tag and when I use Online Marketing services, My links might be place on PR Page of other websites. Also, webmasters use Reciprocal or triangular link building for improving their site rankings.So, How Google differentiates, The link which is through paid or link exchange technique. Plz share your views.
