What is Do Not Track?
Do Not Track (DNT) is a mechanism originally proposed and adopted by Mozilla. When turned ON in a browser, the browser sends an additional HTTP Header with every request to the servers. This additional header tells servers that the user does not want to be tracked for behavioral advertisements and other tracking purposes.

All leading web browsers, except Google Chrome, have already introduced the option to change the DNT settings. Users of Firefox, Opera*, Safari and even Internet Explorer can turn-on DNT and enhance their online privacy. Maxthon, a not-so-popular web browser, has gone one step forward to turn-on DNT by default for all users – and there is no option to disable it – after all who wants to disable it! :)
How To Enable DNT in Chrome?
Chrome has not added support for DNT yet, so there is no direct way to enable Do Not Track in Chrome. But, you can install extensions to bring support for DNT in Chrome.
Thanks to the recently introduced WebRequest extension API of Google Chrome, I have created this browser extension which enables DNT in Chrome.
Install this extension from Chrome Web Store. Once installed, this extension adds DNT HTTP header with every outgoing request. To check and verify DNT setting of your browser, simply visit this link.
(*Current stable build of Opera does not support DNT. Opera 12 “Wahoo”, which is currently in beta, has option to enable or disable it).

DNT for chrome is a great extension I must say. But the feature is also provided by many internet security products and anti-virus tools like AVG that integrate with the every browser installed on the system as another external add-on.
Great extension. I was using a similar extension in past, but it was not working correctly.
Thanks!