We like to re-post this one because it’s one of the most eye-opening demonstrations of how your “harmless” Internet surfing is not what it seems. This is a must view to see how your personal information and viewing habits are not “personal”.
Watch and share this video that shows you how your information is being tracked. It is quite scary.
(Then download the “Collusion” add-on for your browser and see what is actually happening to you).
This is the one for Firefox but use Google to see if there is a version for the browser you use: