No Bull Shit, and old hacker acronym which is usually used to signify that the talk will be serious.
User: I need to talk to you, NBS.
User2: ESAD, Noob.
person: "Ay yeoo u lyin"(While laughing)
You: "Foreal Nbs Cuhz
abbreviation for nota bene: used to mark something as particularly important.
The party is tomorrow at 8.
NB: Dress in formal attire.
Netspeak for "No Bullshit".
Kid on Facebook: Does anyone know where I can purchase a copy of earthworm jim for the SNES?
Seller on Facebook: Yeah I got a copy.
Kid on Facebook: NBS?
Seller on Facebook: NBS. Inbox for price.