Each virtual or dedicated server has its own Operating System and works independently from the hosting servers of other clients. Updating the Operating system is often neglected, but doing that may have quite a lot of benefits for your sites. The most important reason to use the most recent version is that patches are typically released to repair security holes in the Operating System code, so if you don't install the updates, you risk individuals with malicious intentions to use these holes and to access your content. OS updates are also released for enhanced efficiency of the system as a whole and for much better compatibility with the hardware on the market, which could directly impact the functionality of your internet sites. If the functionality and the security of your scripts is the reason to update them, you may also find out that their most recent versions require an updated Os in order to operate effectively, thus keeping the OS up-to-date is always a wise idea.