If you get a hosting machine of your own, it will operate independently, so it'll have its own Operating System and you can later install server side apps directly or script-driven websites through a hosting Control Panel. Even though keeping the Os updated is not always considered fundamental, it can be a quite important task for a variety of reasons. A newer Operating system version may have better support for specific hardware, so you could get better performance for the sites and web applications which you install. Your server will also be more protected since updates normally include security patches that deal with small issues which may enable unauthorized people to access your content. Last, but not least, newer script versions, which are also released for both increased security and for additional features, might require a later version of the Os in order to work properly and with their 100 % capabilities.