The root, or super user account, is a special account and user on UNIX and Linux systems. Super user permissions are required in part because of the restrictive file permissions assigned to important system configuration files. You must have root permission to edit these files or to access or modify certain devices (such as hard drives). When logged in as root, you have total control over your system, which can be dangerous.
When you work in root, you can destroy a running system with a simple invocation of the
rm command like this:
matthew@seymour:~$ sudo rm -rf /
This command line not only deletes files and directories but also could wipe out file systems on other partitions and even remote computers. ...