Google recently launched behavioral targeted ads for AdSense. This means AdSense displays adverts not only on the context of the webpage, but on the context of your browsing history. The aim is to provide more relevant and efficient adverts, but tracking cookies being used across hundreds of thousands of websites raises obvious privacy issues, as Google can use this information to log website you have been on.
Usually, the Electronic Frontier Foundation is very critical of big corporations who intrude on people's privacy, but their criticism was not very harsh. Why? Because Google has developed a web browser plug-in that permits users to opt-out of this scheme.
The plug-in is available for Internet Explorer and Firefox and modifications to browser preferences in Chrome and Safari also allow people to opt-out. Google also maintains an 'Ad Preferences Manager' which allows this tracking cookie to be disabled until the next time cookies are wiped.
There are several reasons to disable these cookies. Firstly, you may not entrust Google with your details. Secondly, adverts based on past browsing may be displayed to other users of the computer... not perfect if, for example, you were buying a present for a family member and they are suddenly swarmed with advertisements about it!
Most tracking cookies can be disabled if you modify browser settings. In Firefox, for example, in Preferences>Privacy, you can refuse to 'accept third party cookies'.
Update: Disabling third party cookies can be an effective option to disable tracking on the web. All web browsers ship with such an option. It is furthermore possible to install add-ons like NoScript or Google Privacy to block further tracking attempts on the web.
Mozilla about a year ago started to include a "do not track" header in Firefox that informs websites on connection that the user does not want to be tracked. Companies like Google or Microsoft will implement a similar option into their browsers.
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.