Debian is a well-known Linux distribution, that is used mainly on PC's, still a lot of people have begun using it lately as a web server Operating System too, due to the stability and protection it provides. The latter is a direct result the fact that Debian is developed and supported by countless qualified volunteers around the globe, so any patch that's needed to fix some issue is released in a couple of days. The very same community will also help with any question or trouble which a user may ever experience, as they can be contacted through electronic mail using e-mail lists and a qualified response will be sent in no more than 15-20 minutes. The advantage here is that your queries will be answered by the same people who have developed the Operating System itself and they have a detailed knowledge of how it functions. As Debian is absolutely free, you won't 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 the Operating System and the 30.000+ software packages that are available for it.