If you get a hosting server of your own, it will operate independently, so it'll have its own Os and you could later install server side apps directly or script-driven internet sites via a hosting Cp. Though keeping the Os updated isn't always considered a necessity, it can be a really important task for a number of reasons. A more modern OS version might have better support for specific hardware, so you could get better performance for the internet sites and web applications that you install. Your server shall also be more safe as updates typically include security patches that deal with small issues which may allow unauthorized people to access your content. Last, but not least, current script versions, which are also released for both increased security and for additional features, may need a later version of the Os in order to work correctly and with their 100 % capabilities.