Similar to noob
It's like noob as it can be used as an insult when commenting on an act someone did (something stupid)
*It's also like noob as you can fool with newbs. (It is the reason why the definitions are so messed up)
You can call a friend a nub.
You use nub when you are talking about someone who is definitely NOT a newb.
Un-like noob which is used in almost every situation under the sun)