A virtual or a dedicated server is a standalone machine, which has its own Os and keeping the latter up-to-date is an essential, albeit underestimated task. Not only can an update enhance the functionality of your sites, but it will also save you lots of troubles down the road. An update may be released for a variety of reasons, the most widespread being to fix newly found security holes, which may allow third-party people to access and modify the content that you have on the server. You might also see an improved efficiency of your web applications as updates may also be released for better compatibility between the Os and the configuration it functions on so that you can get the most out of the hardware. Also, if you keep your programs up-to-date, they could also require a later Operating system version that will have the necessary software dependencies and will enable them to operate properly.