If you have root-level access to a hosting server, this means that you will have full control over it. In other words, you can set up any server-side app whatever the changes that it will make to the software setting on the server, and you are able to both access and modify any kind of file, including system files, and modify any settings. This can be done by connecting to the server as a root user that has full privileges to do all these things and also to generate other users, including users that also have full privileges. This connection can be established using a web-based graphical interface or a Secure Shell console. For security reasons, it is recommended that you make another user for your daily work and employ the root user only when you need to modify the server or to install software which may be required by a script-driven app that you wish to run.