Mark Zuckerberg is watching your every move on Web, and this time even more closure. Facebook recently announced it has plans to use information from our Web browsing and app history to deliver more targeted advertisements to us. The company can’t track your online activity while visiting any website, but only those that have Facebook “LIKE”, “Recommend”, “Share” buttons across the web, and I think almost all have at least one included in it. Any website with a Facebook buttons, like the one you reading right now, or any website that allows you to login with your Facebook account is somehow connected to Facebook.
Source: https://thehackernews.com/2014/06/facebook-to-use-your-web-browsing.html