Debian is a widespread Linux distribution, that's used mainly on desktop machines, but numerous people have begun using it lately as a web server Operating System too, due to the stability and protection it supplies. The latter is a direct result the fact that Debian is developed and supported by numerous qualified volunteers worldwide, which means that any patch that's required to fix a particular issue is released in a couple of days. The same community will also help you with any question or issue that a user may ever experience, because they can be contacted via electronic mail using e-mail 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 answered by the same people who have made the Operating System itself and they have an in-depth knowledge of how it functions. As Debian is absolutely free, you won't have to pay any kind of license fees to use it and you'll be able to personalize it as much as you want or need. This is valid for the Operating System and the 30.000+ software packages which are readily available for it.