Last week, Mark Zuckerberg testified in front of the US Congress. He answered more than 500 questions and promised that we would get back on the 40 or so questions he couldn’t answer at the time. We’re following up with Congress on these directly but we also wanted to take the opportunity to explain more about the information we get from other websites and apps, how we use the data they send to us, and the controls you have. I lead a team focused on privacy and data use, including GDPR compliance and the tools people can use to control and download their information.
When does Facebook get data about people from other websites and apps? Many websites and apps use Facebook services to make their content and ads more engaging and relevant. These services include:
Social plugins, such as our Like and Share buttons, which make other sites more social and help you share content on Facebook;
Facebook Login, which lets you use your Facebook account to log into another website or app;
Facebook Analytics, which helps websites and apps better understand how people use their services; and
Facebook ads and measurement tools, which enable websites and apps to show ads from Facebook advertisers, to run their own ads on Facebook or elsewhere, and to understand the effectiveness of their ads.
When you visit a site or app that uses our services, we receive information even if you’re logged out or don’t have a Facebook account. This is because other apps and sites don’t know who is using Facebook.