Numerous websites have implemented the Facebook “Like” button to let Facebook members share their interests, thus promoting websites or news items. It is, thus, an important business tool for content providers. However, the tool is also used to place cookies on the user’s computer, regardless of whether a user actually uses the button when visiting a website. This allows Facebook to track and trace users and to process their data. It appears that non-Facebook members can also be traced via the Like button. This means that Facebook’s data collection practices reach far beyond their own platform and membership. Owing to the proliferation of Like buttons, Facebook has a potential connection with all web users. Web activity can be linked to individual accounts, or a separate data set can be created for individuals who are not (yet) Facebook members. The hidden collection of data on browsing behavior and the creation of individual data sets has ramifications for the privacy of individuals. Privacy issues arising from thirdparty cookie use and connectivity of web activity and devices will be discussed, using the technical process behind the Facebook Like button as an example.