And when you logged on Google then it will not only gives you search results for your current activity but also give you search results as per your previous history you interests that Google continuously keep tracking on you.
It is basically to benefit their advertising network and their advertising partners. Actually there are many rumors related to this policy, people are thinking it will steal their all personal information and publish them publicly and provide to advertising companies. But I think Google will not do because it has a large network of their users and it may discourage their users to trust on Google.
Mozilla addons Collusion is an experimental add-on for Firefox and allows you to see all the third parties that are tracking your movements across the Web, Mozilla said. It will show, in real time, how that data creates a spider-web of interaction between companies and other trackers. This addon give you a graphical representation on who are keep watch on you.
Mozilla addons Collusion will allow us to pull back the curtain and provide users with more information about the growing role of third parties, how data drives most Web experiences, and ultimately how little control we have over that experience. Mozilla aims to build up a database of the worst offenders – and make the data available to privacy campaigners.