Debian is an Operating System that uses the Linux kernel. Even though it is usually installed on desktop computers, it is being used on more and more web servers too. The reason is that it is very stable, so a server running it won't need to be restarted for months. Debian is also considered to be one of the most risk-free Operating Systems to be found, as security patches are released within days after a problem is discovered. This is possible since thousands of qualified developers work for the Debian project on a voluntary basis and not only do they work on the OS itself, they also provide 24/7 support by using special e-mail lists and reply within twenty minutes to any question. In this light, you will obtain top-level support directly from the developers who know their own platform in depth, and not from a third-party support team. Debian is also among the Linux distributions with the highest number of packages - more than 30,000. Since the Operating System costs nothing to use, you are able to modify both the core as well as all the packages in any way you see fit. Furthermore, you will not need to pay any kind of license fees.