Please look at this page for basic commands or  basic reference LINUX COMMAND REFERENCES
Note: You have a limited number of processes that you can create. Once you have exceed that number, you will not be able to remotely log into the machine.

PS  process status
In order to kill a process, first we need to know  the process ID (PID).
To get the process id, use the report process status command "ps".

 prompt# ps -ef | grep janedoe

This will print the processes running for the current user, jadedoe:

UID        PID  PPID  C STIME TTY          TIME CMD 
janedoe   2233  2231  0 16:57 ?        00:00:00 /usr/sbin/sshd
janedoe   2234  2233  0 16:57 pts/0    00:00:00 -sh
janedoe   2254  2234  0 16:57 pts/0    00:00:00 ps -ef
janedoe   2255  2234  0 16:57 pts/0    00:00:00 grep janedo

KILL terminate a process
KILLING YOUR PROGRAMS IS IMPORTANT BECAUSE IT RELIEVES
THE WORKLOAD ON THE CPU. THEREFORE MAKING DATA PROCESS
FASTER FOR EVERY USER. here is how to do it:

prompt# kill -9 [PID]

NOTE: characters in the [] brackets represent actual values.
For example this command terminates "/usr/sbin/sshd":

prompt# kill -9 2233

SPECIAL NOTE: If all else fails, then use:

prompt# kill -9 -1
 
or

prompt# pkill -U [username]

prompt# pkill -U [username];pkill -U [username]

 
 CTRL-C   vs  CTRL-Z
Why are they useful to know?

   Ctrl-C   is used to terminate a job or process.  You would usually use this
   when  a program crashes, or  when you are executing a file that gets out of control
   (example infinite loops).

   Ctrl-Z   is used for running a program in the background
   NOTE  this will not terminate your job (process)!

How do I use it?
     HOLD  key:   Ctrl
           and key:  c
      Simultaneously (at the same time)

Know everything with MAN
Do you want to know more or do more with a  command?
If so use man to tell you lots of information about  a command.
man even explains how to use man. Here is how to use it:

prompt# man command

For example if I want to know what options the command "ls"
has use this:

prompt# man ls

And a page of text appears.  To quit viewing a  man page just
type the letter  "q".  This should bring you back to the prompt.
 
 

Department of Computer Science
Howard R. Hughes College of Engineering
UNLV