Word USED Very frequently BY Everyone
It has variety of meanings. Most often it is used as a colloquial way of saying "yes", it can also express understanding or agreement. For example "no nie!" ("no no!") can express disbelief, disappointment or even anger. It always depends on the context.
"Jesteś gotowy?" "No."
"Are you ready?" "No." (instead of "yes")
Submitted August 2020 by joannaea