NPCs can be given Waypoints to dictate their motion.
Waypoints are created by a Waypoint Provider. You can change providers using the /waypoint provider [provider] command.
The current Providers are:
Linear (default) - Sends the NPC to each stored waypoint in sequence.
Wander - The NPC wanders around randomly.
Guided - The waypoints are split into destination waypoints and guide waypoints. Destination waypoints are chosen randomly and pathed to using a combination of the guide waypoints.
For the linear waypoint provider, triggers can be added to pause the NPC at certain waypoints, change their speed or say something at a waypoint. More information can be found by typing 'triggers' in the waypoint editor.