Proper Terminology: NPCs exhibit highly restricted behaviour and exhibit predictable responses to our interactions. They are confined to the parameters set by their code and lack consciousness or vitality, a fact that becomes evident only when real players engage with them.
Laymen Terminology: A person who is an empty shell, who lacks internal substance and has no character or personality. They live to exist, and have no purpose.
Street Terminology: Fake ass b*tch.
Carla: How do you manage dealing with Non Player Character or NPC?
Jake: You just have to allow it.
Carla: Do you mean, just accept it?
Jake: Yeah. They're like born without a soul.