Debian is a Linux distribution, that is widely used for desktop machines, however it's been gaining in popularity as a server Operating System over the last few years too. It's very stable and secure, because fixes are released in just a few days after a problem is discovered. Debian has a vast support community, so when you have any questions or troubles with the OS or with some of the 30,000+ packages it includes, you can easily contact the developers without delay via electronic mail using special e-mail lists and receive a reply in just 15-20 min. The Debian community offers the top level of support possible, because all your questions will be handled by exactly the same people that built Debian in the first place, so they have a thorough knowledge of how their own system functions. As the Operating System is free to use and distribute, no license charges will be added to your hosting fees and you can change the code files and any other software that you install without restrictions, so as to optimize the software environment for your web sites. In addition, Debian performs very well on any kind of hardware, as it is light and efficient and doesn't require a lot of memory.