The UPS and the diesel generator are 2 means for keeping a web server functioning if there are problems with the main source - a disruption or unreliable current which cannot keep the machine functioning properly, for instance. UPS is an abbreviation for Uninterruptible Power Supply, although it can often be referred to as Uninterruptible Power Source too. The UPS is, essentially, a highly effective battery that is attached to the web server and to the power network constantly, so in the case of any blackout, it is already working, which enables the hosting server to continue operating without losing any information. The diesel generator is an engine that will power up the entire data center. It does take some time to begin working and it is the UPS that gives it this time. Those 2 power solutions are a necessity for any facility or service provider that wants to prevent data loss and hardware damage as a result of an unexpected power problem.