If you get a hosting server of your own, it will work independently, so it will have its own Operating System and you can later install server side applications directly or script-driven sites via a hosting Cp. While keeping the Operating System updated is not always considered fundamental, it can be a very important task for a variety of reasons. A newer Operating system version might have better support for specific hardware, so you could get better performance for the sites and web applications you install. Your server shall also be more secure because updates usually include security patches that deal with small problems that may enable unauthorized people to access your content. Last, but not least, more modern script versions, which are also released for both improved security and for additional features, may require a later version of the Operating System in order to work effectively and with their 100 % capabilities.