>>mistri+(OP)
Makes sense to me. He basically made a system that detects when someone else is using your computer by e.g. comparing patterns of mouse and keyboard input to your typical usage. It would be useful in a situation such as if you left your screen unlocked and a coworker sat down at your desk to prank you by sending an email from you to your boss (or worse, obviously). The computer would lock itself as soon as it suspects someone else is using it instead of you.