What do you mean by nice value?

      Nice value is the value that controls {increments or decrements} the priority of the process. This value that is returned by the nice () system call. The equation for using nice value is:

Priority = (“recent CPU usage”/constant) + (base- priority) + (nice value)

Only the administrator can supply the nice value. The nice () system call works for the running process only. Nice value of one process cannot affect the nice value of the other process.