UPS

 UPS (uninterruptible power supply)

 UPS stands for uninterruptible power supply. It UPS is a device containing one or more batteries, and some circuitry to provide continuous power to a computer, even in the case of power failure. This prevents the computer from switching off abruptly, thus giving you time to save your work and shutdown properly. the computer can only continue operating normally for as long as the UPS' battery lasts.

 Modern UPS not only keep your computer on, but also ensure that uninterrupted power devoid of surges, spikes and sags in the voltage and frequency changes comes to the PC.A continuous UPS is one where the system is always running off the battery, and it is constantly being charged by the power outlet. A UPS can also be intelligent; informing your PC when the power cuts off so that an automated backup and shutdown can take place if the computer is unattended.