UPSs and diesel generators are two backup systems that are kept by web hosting service providers within their data centers in case there are interruptions in the primary power supply or the current is unstable and unable to sustain the appropriate functioning of the machines based within the facility. UPS is short for Uninterruptible Power Supply or Uninterruptible Power Source and it's a highly effective battery that works non-stop. It's connected to both the electrical power network and the web servers constantly, so anytime the power stops, the UPS is already operational, which prevents the machines from going down even for a second. The diesel generator is definitely an engine which can deliver the necessary electric power to keep the servers operational for a longer period of time. In case there is an outage, the UPS gives the needed time for the diesel generator to start and then to take over until the main source is restored.
