- lsmod, what are the modules returned by lsmod? what do they do?
- lsof -p 1, what is the proc filesystem, what are the files under it. 
  - /proc/self magicly link to calling processes pid
- lsof /home/cris - display files open in that directory
- check it http://www.linuxguide.it/command_line/linux_monitoring_and_debugging-c26_en.html