If you have root-level access to a server, this means that you will have full control of it. That is to say, you can set up any server-side application no matter what the changes that it will make to the software environment on the server, and you can both access and update any kind of file, including system files, and change various settings. This can be done by connecting to the server as a root user which has full privileges to perform the aforementioned things and to create other users, which includes users who also have full privileges. The connection can be established through a web-based graphical interface or a Secure Shell console. For safety reasons, it's recommended that you create another user for your everyday work and employ the root user only when you need to customize the server or to install software which may be required by a script-driven app that you want to run.