If you get a hosting server of your own, it will operate independently, so it will have its own Operating System and you can later install server side applications directly or script-driven websites via a hosting Cp. Though keeping the Os updated is not always considered fundamental, it can be a rather important task for a variety of reasons. A more modern OS version may have better support for specific hardware, so you might get better performance for the websites and web applications that you install. Your server shall also be more secure because updates normally include security patches which resolve small issues that may permit unauthorized people to access your content. Last, but not least, more modern 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 correctly and with their full capabilities.