When you have root-level access to a server, it means that you will have full control of it. In other words, you can set up any server-side application regardless of the changes that it will make to the software setting on your server, and you are able to both access and change any kind of file, including system files, and change any settings. This can be done by connecting to the server as a root user who has full privileges to do all these things as well as to create other users, which includes users who also have full privileges. This particular can be established with a web-based graphical interface or a Secure Shell console. For safety reasons, it is recommended that you create one more user for your daily work and use the root user only when you have to modify the server or to install software which may be required by some script-driven app that you wish to run.