Debian is a Linux distribution, that's widely used for desktop computers, but it has been gaining in popularity as a server OS during the last couple of years as well. It is very dependable and safe, because fixes are released in a few days after an issue is discovered. Debian has a large support community, so if you have any questions or troubles with the OS or with any of the 30,000+ packages it comes with, you can contact the developers without delay via electronic mail using special e-mail lists and receive a reply within 15-20 min. The Debian community supplies the best level of support possible, because all of your questions will be handled by the same people that built Debian in the first place, so they have an exhaustive knowledge of how their system works. Since the Operating System is free to use and distribute, no license costs will be included with your web hosting fees and you'll be able to change the code files and any additional software that you install with no restrictions, in order to optimize the software environment for your web sites. Furthermore, Debian performs really well on any kind of hardware, because it's light and quick and does not require much memory.