The UPS and the diesel generator are 2 means for keeping a server operational if there are problems with the primary source - a disruption or unstable current which cannot keep the web server functioning properly, for instance. UPS is an abbreviation for Uninterruptible Power Supply, although it is frequently referred to as Uninterruptible Power Source too. The UPS is, in essence, a highly effective battery that is attached to the web server and to the electric power network constantly, so in the case of any disruption, it is already operating, which enables the server to continue doing the job without losing any information. The diesel generator is an engine which will power up the entire data center. It needs some time to begin working and it is the UPS which provides this time. Those 2 power solutions are a requirement for any facility or provider that wants to avoid data loss and hardware damage caused by an unexpected electrical power problem.