Non Player Characters are characters in a role-playing game, video game, or simulation that are controlled by a player or a controller. They are typically programmed to follow a set of specific rules, behaviors and scripts to interact with the game world and the other characters in the game.
This character is also a part of our everyday life. We don't recognize or know what they are because they are not programmed to interact closely with us. In the Matrix movie, these characters were easily taken over by the Smith's or other Programs. These NPC's are present in all walks of life, businesses, corporations, governments, politicians and in the worlds' population. They have no soul and therefore have no Divinity. They are part of the Hive Mind Program and don't break from agendas. You can try to convince the NPC's of the truth, so to speak, but they cannot comprehend it because they lack the emotions, such as compassion, to care. They have some degree of autonomy but their actions are still determined by rules, script, game or simulation. They may make decisions, but these decisions are predetermined or limited to a certain set of outcomes. They can interact with us through conversation, trade or other forms of communication.
The usage of the term NPC has taken on the meaning of a much more broader term, often used to refer to people who are perceived as lacking originality or independence. Also those who mindlessly repeat talking points or beliefs. When this term is used, it is considered a derogatory term, it is referring to the aforementioned characteristics and a list of many more.
Dolores Cannon spoke of the Backdrop or Background People. They only exist to fill the scenes of your everyday life. When you are no longer in that scene, neither are they because they do not exist.