Debian is a well-known Linux release, that's used mainly on desktop computers, but lots of people have begun using it lately as a web server OS too, because of the stability and protection it supplies. The latter is a consequence of the fact that Debian is developed and supported by thousands of qualified volunteers around the globe, so that any patch which is necessary to fix some issue is released in a couple of days. The same community will also help you with any question or issue which a user may ever encounter, as they can be contacted through electronic mail using mailing lists and a qualified response will be sent in no more than 15-20 min. The advantage here is that all of your questions will be responded to by the same people who have created the Operating System itself and they have a detailed knowledge of how it functions. As Debian is provided for free, you will not need to pay any license fees to use it and you can personalize it as much as you want or need. This is valid for both the Operating System as well as the 30.000+ software packages which are available for it.