Every virtual or dedicated server has its own Os and operates independently from the hosting machines of other clients. Updating the OS is frequently overlooked, but doing that may have a wide range of benefits for your websites. The most essential reason to use the most recent version is that patches are usually released to repair security holes in the Operating System code, so if you don't install the updates, you risk people with destructive intentions to use these holes and to gain access to your content. OS updates are also released for improved efficiency of the system in general and for far better compatibility with the hardware available on the market, which could instantly influence the performance of your websites. If the performance and the security of your scripts is the reason to update them, you may also know that their newest versions require an updated Os to be able to function effectively, thus keeping the Operating system up-to-date is always a good idea.