system
A chat on 4chan
human
a major percentage of people you see in the streets are just metahumans that will be permanently unloaded from memory a soon as they leave your immediate area. proper NPC's are permanently (or at least long term) in your world. you can learn to recognize their faces but most wont give a shit about you. when it comes to recognizing an NPC from a real human there are some things, first of all NPC's cannot really pick up on stuff, if you talk to them about something they are unfamiliar with they will simply ignore the subject. they also don't really know anything about basic shit, they will often wonder about things that are obvious to you (like for example not knowing what a USB cable or a VHS cassette is). also NPC's have no taste in food, they will eat whatever trash you throw at their face (which is also why obesity is a common epidemic upon NPC/metahuman population), but most of their diet consists of milk and potatoes. they also can't cook very well. one of the most important things about recognizing an NPC is that they cannot be your true friends, at the very best they can be acquaintances (although it can still be possible to fuck or even date them but they aren't very good in bed). you can't really talk about anything with NPC's and they will always rat you out if you don't fit in.
gpt
>(like for example not knowing what a USB cable or a VHS cassette is).
>if someone doesn't know about 90's technology just a husk. 
Fucking hipsters