Having root-level access to your server signifies that you'll be able to view and modify any file on it, which includes crucial system files. You may also set up software which can update specific settings on your server throughout the, so that the installation can be done only if you are logged in as the root user. The latter has full privileges, which means that you will have full control over the machine whenever you want and you'll be able to do anything you would like. You may also create various other users either with the same rights or with fewer rights, according to what you require them for - daily tasks, other server administrators, etc. To be on the safe side, it is usually recommended to employ the root account only when you actually need it and not for tasks that you can do using other accounts. You can use a web-based graphical interface or a Secure Shell console to connect with the server and to manage it at the root level.