Debian is a Linux distribution, which is widespread for desktop computers, but it's been gaining popularity as a server OS over the last couple of years too. It's very stable and risk-free, due to the fact that fixes are released in a couple of days after an issue is discovered. Debian has a vast support community, so when you have any questions or problems with the OS or with some of the 30,000+ packages it features, you're able to contact the developers straight away via electronic mail using special e-mail lists and receive a reply within 15-20 minutes. The Debian community provides the best level of support possible, since all your questions will be handled by the very same people that made Debian in the first place, so they have an in-depth knowledge of how their system operates. Because the Operating System is free to use and distribute, no license costs will be added to your web hosting fees and you'll be able to modify the program code files and any additional software which you install without any restrictions, in order to optimize the software environment for your websites. In addition, Debian performs very well on any hardware, as it's light and quick and doesn't require much memory.