The UPS and the diesel generator are two instruments for keeping a server operational in case there are difficulties with the primary power supply - an interruption or shaky current that cannot keep the hosting server functional, for instance. UPS is an abbreviation for Uninterruptible Power Supply, though it is sometimes referred to as Uninterruptible Power Source also. The UPS is, in simple terms, an efficient battery that is attached to the hosting server and to the electric power network at all times, so if there is any disturbance, it is already functioning, which allows the server to keep on running without losing any information. The diesel generator is an engine that will power up the whole data center. It needs some time to begin working and it is the UPS which gives it this time. Those two power solutions are a requirement for any facility or service provider that wants to stop data loss and hardware damage resulting from an unexpected electric power issue.