Each virtual or dedicated hosting machine has its own Os and works separately from the hosting machines of other clients. Updating the Operating system is often ignored, but doing that may have a wide range of benefits for your sites. The most important reason to employ the newest version is that patches are usually released to deal with security holes within the Operating System code, so if you do not install the updates, you risk people with destructive intentions to exploit these holes and to get access to your content. OS updates are also released for much better performance of the system in general and for better compatibility with the hardware available on the market, which could instantly impact the performance of your internet sites. If the functionality and the security of your scripts is the reason to update them, you may also know that their most up-to-date versions require an updated Operating System to be able to operate properly, therefore keeping the OS up-to-date is always a wise idea.