The internet is a very porous place with no place to hide. Even so, everybody is trying to snoop in on hapless web surfer without any reason. Sometimes its the NSA or your local authorities other times it may be some malware or bots which are trying to piece together the way you surf the net and let loose their vicious armaments.
The most popular tracking device is a cookie. Every time you visit any site, including mine a cookie is generated which then helps the concerned party to use it for your or their benefit. In my case, Google cookies are generated so that you can get better search with point to point results. However some anti social elements as well as authorities use them to deduce your web browsing habits. Up until now you could not possible know who was tracking your web history. Firefox has developed a experimental plugin called Lightbeam. Lightbeam uses a tracking extension called Collusion which maps the cookies used each website you visit during your sojourn on the internet. You can check the vast potential of the tracking experiment by clicking on the Collusion link. Keep it open in one browser window and visit a view sites in another and you’ll see new nodes pop out on the visualisation as new cookies are discovered. Ones marked in red are confirmed trackers.
Mozilla has now come up with a nice little add-on or plugin called Lightbeam which you can download in your Mozilla Firefox browser. The good news is that the experiment is totally open source so it will soon be ported to Chrome as well.