When Facebook made its timeline profiles mandatory, many users cringed as they relived past relationships and embarrassing nights out. So did all of their friends and family, who could now see what was probably best forgotten. Suddenly, it became apparent just how well Facebook remembers. It remembers that time you “liked” Budweiser, and it remembers you joining the “Bring Back Sailor Moon!” group when people still joined Facebook groups. Chances are, those memories are still haunting the side of your newsfeed.
Facebook makes most of its money from advertisers. In 2010, the company violated its own stated privacy policies by selling user information to vendors to help target their sales. Some users found this out when they saw their own smiling faces next to advertisements for products they “liked”.
This trend is particularly unnerving to parents. More than five million Facebook users are under the age of 13, and their “likes” are already being tracked.
Source: Facebook Privacy Fail