If you get a server of your own, it will operate independently, so it will have its own Os and you'll be able to later install server side applications directly or script-driven internet sites through a hosting Cp. Although keeping the Os updated isn't always considered a necessity, it can be a rather important task for a variety of reasons. A newer Operating system version may have better support for specific hardware, so you may get better performance for the websites and web applications which you install. Your server shall also be more safe because updates often include security patches that fix small issues that may permit unauthorized individuals to access your content. Last, but not least, current script versions, which are also released for both improved security and for additional features, may need a later version of the Operating System in order to work effectively and with their 100 % capabilities.