The back-up power supply is a device which can power a computer in case of a power outage or if the power cable is inadvertently unplugged while the computer is in operation. The power cable from the computer plugs into the backup power supply and another cable connects the supply to the electrical outlet. When electricity is coming through to the backup power supply, it is carried through to the computer. In case no electricity is coming through, it is supplied by a battery in the power supply housing. A power switch on the housing allows this backup power to be turned off when not desired.
