• Every running program has at least one associated process;
• Use the ps command:

      ps        # ...show my processes...
      ps ux     # ...show more detail...
      ps aux    # ...show everyone's processes in detail...

Example

USER  PID %CPU %MEM  TTY   STAT START  TIME COMMAND

rcs  3036  0.0  0.3  ?      S   Oct17  0:18 sshd: rcs@pts/0  
rcs  3037  0.0  0.1  pts/0  Ss  Oct17  0:00 -bash
rcs  3039 99.3 33.5  pts/0  Sl  Oct17  3:03 /usr/bin/firefox
rcs  3119  0.0  0.7  pts/0  S   Oct17  0:33 emacs
rcs 20846  0.0  0.0  pts/0  R+  10:31  0:00 ps ux

Kill!

• What is slowing the system down? kill 3039, or kill -9 3039.