Having full root-level access means that you'll be able to access and customize any file on a selected server, in addition to all the system files, and to change system settings or set up server-side software that may be needed by specific scripts and even offline apps in order to function appropriately. A server is accessed at the root level through a root user, who has full privileges to perform any of the abovementioned things. Your root user may also create various other users. For security reasons, you're advised to have a different account for day-to-day tasks and to use the root account only if you actually need to perform a particular task on your server. The root-level access function offers you full control over your server from any kind of location, given that you have the user credentials.