Debian is an OS that uses the Linux kernel. Even though it is usually set up on personal computers, it is being used on a growing number of web servers as well. The reason is that it is really stable, so a server running it won't need to be restarted for months. Debian is also regarded as being one of the most protected Operating Systems available, since security patches are released within days after a problem is discovered. This is possible because thousands of experienced developers are working for the Debian project on a voluntary basis and not only do they work on the OS itself, they also provide 24/7 support via special mailing lists and respond within twenty minutes to any question. In this light, you'll receive an outstanding level of support directly from the developers who know their own platform in depth, and not from a third-party support team. Debian is also one of several Linux distributions with the highest number of packages - over 30,000. Since the Operating System costs nothing to use, you'll be able to modify both the core as well as all the packages in the way you see fit. In addition, you will not have to pay any kind of license fees.