Having full root-level access signifies that you'll be able to access and modify every file on a particular server, in addition to all the system files, and to change system settings or set up server-side software which may be necessary for specific scripts and even offline apps to function appropriately. A server is accessed at the root level through a root user, who has full privileges to perform all of the abovementioned tasks. Your root user may also create other users. For security reasons, you are advised to have another account for routine tasks and to use the root account only if you actually need to do some task on your website hosting server. The root-level access feature will give you full control of your server from almost any location, as long as you know the user credentials.