Security_Key lets you create a \"Security_Key\" (similar to an ignition on a car) out of a USB Flash Drive. This \"Security_Key\" must be present when the machine boots or it willl immediately put the display to sleep. Also, if you eject the disk, your computer will immediately sleep. Now, you cannot wake the machine up untill the \"Security_Key\" is re-inserted.
I recommend making a clone of this \"Security_Key\" on a CD and storing somewhere for emergency situations.
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