Mozilla and Google take steps to give people privacy online. Web sites then decide whether to grant or desire to continue collecting data for purposes such as targeting Internet advertising. Google launched software for its Chrome browser extension that allows users to choose not to be followed. Microsoft plans to increase privacy options in next version of Internet Explorer 9 (IE9) IE9 will be integrated into a trial version of the Internet browser this year. Internet Explorer is the most used browser in the U.S., followed by Mozilla Firefox, Google Chrome and Apple Safari.
Source: https://thehackernews.com/2011/01/google-and-mozilla-to-make-do-not-track.html