I hope you won't be able to kill them all, it cannot make any sense, anyway, but why would I care if you want to screw up your system? You will reboot it (because you hardly will be able to work at all if you kill some of the critically important applications).
Whatever. Those are not applications, but processes. You can get all processes using
and kill a process using
. Please see:
This is all you need, enjoy. Let the OS doomsday begin!