If you get a hosting machine of your own, it will operate independently, so it'll have its own Os and you'll be able to later install server side applications directly or script-driven sites through a hosting Cp. While keeping the Os updated isn't always considered a necessity, it can be a quite important task for a number of reasons. A newer OS version could have better support for specific hardware, so you may get better performance for the sites and web apps that you install. Your server will also be more protected since updates normally include security patches that deal with small problems that may allow unauthorized people to access your content. Last, but not least, more modern script versions, which are also released for both enhanced security and for additional features, may require a later version of the Operating System in order to work properly and with their full capabilities.