I am trying to "reload" firefox at 5am everyday.
was looking at the crontab and the way it works, however i'm not sure how to kill firefox first and then reopen it.
Any suggestions?
killall firefox
Note: do not use killall on an HP-UX system (or Solaris) 
I use ubuntu so there shouldn't be a problem.
do i need to be root to kill firefox?
or crontab is launched by root?
You don't need to be root, you have to be the user that starts the process.
You can schedule cronjobs as a regular user if it hasn't been disable.
Just tried killall firefox, it says:
firefox: no process killed
Anyother suggestions?
Then firefox wasn't running
Does your OS have a program called timeout? It's one of gnu-coreutils. Run firefox with timeout set to kill it after a certain period.