Lightbeam: an add-on to track those who are tracking you
There has been a lot of talk about online privacy and websites tracking users and their behavior online. Apart from sites which track us directly, there are many third party companies which collect our data and track us -- be it about our buying or reading preferences or even our casual browsing habits.

But how do we know who has been tracking us? Is it only giants like Facebook and Google, or others too? Lightbeam is a Firefox add-on developed by Mozilla foundation which visualizes the websites which track you, to give you first hand information about your trackers.
Lightbeam was released last year during MozFest and is developed with the help of Ford Foundation and the Natural Sciences and Engineering Research Council, and aided by faculty and students of the Emily Carr University of Art and Design Canada.
Lightbeam works in four ways. It helps the user visualize the web in real time. As the user downloads the add-on and installs it, it starts gathering the data to create a visualization of the websites directly, as well as all the third party sites which place their trackers on those sites. This can be observed by the triangle nodes on the main screen once you click on the extension.
It also helps the user analyze data and find out information about each third party tracker site, such as in which country the site is hosted and on which site it is plugged in. It also gives the user the ability to save data or reset the data and start afresh if it becomes too cumbersome. It also helps users block the sites that track them, and have a look on their tracking activities. As the data tends to get clogged after a period of time, one can filter it based on daily or weekly visualizations.
As soon as I installed Lightbeam, small triangles started popping up around the sites which I had visited. The sites which were visited were shown in circles and the third party trackers were depicted as triangles on the graph. It is quite interesting to see how these sites are interlinked with each other. In just a day of browsing 63 websites, I was shown that around 336 sites were collecting my data indirectly.
Users can also contribute the data stored in their browser to the Lightbeam database. This will help the team get a bigger understanding of how these websites are connected to each other. The Lightbeam add-on is open source and anyone can view and experiment with the code base which is freely hosted on Github. The Aim of Lightbeam is to raise awareness, promote analysis and, ultimately, affect change in the area of privacy.
Download Lightbeam here.