Non-player characters are any characters in the game world that are not controlled by the player. NPCs are controlled by Radiant AI, a complex system in which NPCs move about the world in a non-scripted, lifelike manner and perform daily tasks including, shopping or hunting for food, going to church, painting, or even going on a mission of assassination. An NPC can come in many shapes and sizes and be any playable race.
The term "NPC" refers to all humanoid characters, meaning all races.
When hovering the cursor over certain NPCs, a crown icon indicates that the character is an essential NPC, and cannot be killed. They can still be fought and knocked unconscious, but they will eventually rise again. This method can be used as a way of gaining experience, as the character will not remember the attack, and the player will not suffer any consequenses of it apart from either a prison sentence or a bounty.
When in combat with an NPC, they are able of chasing the player as they run through rooms, caves or wilderniss. They can flee from the player when they are about to be defeated, or if they have been demoralized.