1. The act of restarting a computer system by disconnecting and reconnecting its power source. Wait, don't unplug your computer just yet—only do a hard reboot if you have to.
2. A film, TV show, or other media franchise that is related to an earlier work or installment but is intended to reinvigorate or update the franchise by dramatically altering many elements of it, such as continuity, aesthetic, tone, and the cast of actors. Christopher Nolan's "Batman Begins" is usually seen as a hard reboot for the caped crusader.