If you get a server of your own, it will work independently, so it will have its own Operating System and you'll be able to later install server side apps directly or script-driven internet sites through a hosting Control Panel. Even though keeping the Os updated is not always considered a necessity, it can be a rather important task for several reasons. A newer Operating system version may have better support for specific hardware, so you may get better performance for the internet sites and web apps you install. Your server will also be more safe because updates typically include security patches that take care of small problems that may enable unauthorized individuals to access your content. Last, but not least, newer script versions, which are also released for both increased security and for additional features, may need a later version of the Operating System in order to work properly and with their 100 % capabilities.