https://motherboard.vice.com/en_us/article/7xkp7a/iphone-8-iphone-x-face-id-legal-privacy-surveillance

Apple executives stood on stage Tuesday and revealed the way we'll unlock the brand new iPhone X: with our faces, using a new feature called Face ID.

It utilizes the selfie camera's "TrueDepth" camera system—a set of sensors and a dot projector—to create a super detailed 3D map of your mug. The dot projector places 30,000 digital points onto your face, capturing the contours and features that make you unique. The system is designed to learn and improve each time it looks at you, and Apple says it should still work even if you change your hairstyle or get glasses.