CentOS is short for Community Enterprise OS. This is one of the best Linux distributions for servers and it's recognized as being one of the most reliable and safe Operating Systems out there. CentOS is open-source software, so you are able to customize it in any way you see fit, adding and removing packages or changing the program code of all of them. It is also free to distribute and use, so you will not need to pay any license fees, which means that the total price that you'll need to pay for a server running CentOS will be much lower as compared to the price for a server working with some other OS. What makes CentOS unique among other Linux distributions is its huge developer community, that will help you get the answer to any question or problem you have. Furthermore, each version that is released officially is supported for ten years, which is a lot longer than with any alternative operating system. What this means is frequent security and stability updates which will provide a dependable software setting for your web applications in the long run.