Debian is a Linux distribution, which is widely used for desktop machines, however it's been gaining in popularity as a server OS during the last few years too. It's very stable and safe, since fixes are released in a few days after an issue is discovered. Debian has a vast support community, so when you have any kind of questions or troubles with the OS or with any of the 30,000+ packages it features, you can easily contact the developers without delay via e-mail using special mailing lists and receive a reply in 15-20 minutes. The Debian community provides the best level of support possible, as your questions will be handled by exactly the same people that built Debian in the first place, so they have a detailed knowledge of how their system operates. Because the Operating System is 100% free to use and distribute, no license costs will be included with your web hosting fees and you will be able to modify the code files and any additional software that you install with no restrictions, so as to optimize the software environment for your sites. Furthermore, Debian performs very well on any kind of hardware, because it's light and effective and does not require much memory.
