ps command shows the state of the process (e.g. Sleeping, Running etc) as also some additional info about.
Among two of these additional options according to the man page are
< high-priority (not nice to other users)
N low-priority (nice to other users)
When playing around with
sudo htop I realized the niceness value can be set to [-20, 19].
What is the threshold that distinguish a nice from a not nice process?