Mozilla Firefox offers a Do Not Track feature that lets you express a preference not to be tracked by websites. This article will explain how to enable Do Not Track.
Tracking is when websites, such as advertising companies, track which websites you go to, and what you search. This can be used for tailoring suggestions & advertising to you personally, for example.
When Do Not Track is enabled, Firefox will tell advertising networks and other websites and applications that you would like to opt-out of tracking for purposes like behavioral advertising.