Debian is a Linux distribution, which is widely used for desktop machines, but it's been becoming more popular as a server Operating System during the last few years as well. It is very stable and risk-free, due to the fact that fixes are released in a couple of days after a problem is discovered. Debian has a large support community, so if you have any kind of questions or problems with the OS or with any of the 30,000+ packages it includes, you can contact the developers without delay via electronic mail using special e-mail lists and receive a response in 15-20 minutes. The Debian community offers the top level of support possible, as all your questions will be handled by exactly the same people who made Debian in the first place, so they have an exhaustive knowledge of how their own system functions. Since the Operating System is absolutely free to use and distribute, no license charges will be added to your web hosting fees and you can change the code files and any additional software which you install without restrictions, in order to optimize the software environment for your sites. In addition, Debian performs very well on any hardware, as it is light and fast and does not need much memory.