This command is used in conjunction with the ps command. With the kill
command you can kill a process(such as elm or nn) which is running on your
account. An example of when you might have to kill a process is when you
are running elm and are kicked out of the internet for some reason. If you
login again and try to run elm, it says that another copy of elm is
running and that you can't start it up. Using the ps command you can get
the pid number of the "old" elm and then use kill to stop the "old" elm
from running anymore. For example if were in this situation and you typed: 

ux1> ps

and got the result:


PID TT STAT  TIME COMMAND
 7268 qm I     0:00 elm
 7530 qM S     0:02 -tcsh[kundert] (tcsh)
 7625 qM R     0:00 ps


You would know that the pid number of the "old" elm was 7268. To get rid
of this process, you would type: 

       % kill 7268

To be really sure to kill it (because sometimes unix doesn't think that
you really do want to kill it), you would type: 

       % kill -9 7268

The -9 will tell it to kill it and kill it hard.