What should I do when a program stops responding on Debian Linux?

Many reasons may cause a program to stop responding. For example, a human typo in a program can be a reason.

I can issue commands on Debian Linux to "clear" this hanging state of the program. Sometimes, clearing this data and restarting a program can help me to continue using this program.

Recently, I upgraded LibreOffice to version 3.5.1. I started LibreOffice 3.5.1. The splash screen appeared and stopped. Nothing worked further.

My commands to clear this hanging program were:

su

ps aux | grep office

I saw:
nameOfTheUser   9655  0.0  0.0  31952  2044 ?   Sl   09:21   0:00 /opt/libreoffice3.5/program/oosplash --writer
nameOfTheUser    9672  0.1  2.1 187040 65252 ?   Sl   09:21   0:00 /opt/libreoffice3.5/program/soffice.bin --writer

9655 and 9672 were the process IDs. I typed:

kill 9655 9672

I restarted LibreOffice and it worked. I did not know why it had stopped at first but I could use it then after "clearing" the hanging processes.

The "kill" command
"kill" is a command for stopping a process or processes. The "kill" command works well in Terminal.

I read this page for such skills.

If the "kill" command had not worked, I would have pressed Ctrl, Alt and Del at the same time to restart the machine.