Simultaneous localization and mapping

Simultaneous localization and mapping is a method of 3D tracking based on camera data of an environment. It uses one or more cameras that are mounted on a rigid body like a headset. It operates based on computer vision, heavily relying on feature detection. It is similar in concept to visual inertial odometry (VIO).

One method of SLAM is ORB_SLAM2. Another method is ORB_SLAM3. Another SLAM-like method is RTAB-Map.

The Hololens 1 and the Magic Leap 1 both use a SLAM-type system for their 3D tracking.

The Oculus Quest 2 uses a tracking system that is some kind of SLAM or VIO.