If you get a hosting machine of your own, it will operate independently, so it'll have its own Os and you could later install server side programs directly or script-driven sites via a hosting Control Panel. Though keeping the Os updated is not always considered a necessity, it can be a quite important task for several reasons. A newer OS version may have better support for specific hardware, so you might get better performance for the internet sites and web apps that you install. Your server shall also be more secure since updates often include security patches which deal with small problems which may permit unauthorized people to access your content. Last, but not least, newer script versions, which are also released for both boosted security and for additional features, might require a later version of the Operating System in order to work effectively and with their full capabilities.