Facebook Collects Data from any Visits to Pages with "Like" Buttons

Computing guru Richard Stallman, creator of the GNU Project and founder of the Free Software Foundation, points out a feature of Facebook that most of us do not know about.

Facebook does massive surveillance, he argues. If there is a "Like" button on a page, Facebook knows who visited that page and it can get the IP address of the computer visiting the page, even if the person is not a Facebook user.  Privacy issues