superuser
also: root, root user, privileged user
The superuser (root) is a special user account with unrestricted permissions to perform any operation on a Linux system, including modifying system files and managing other users.
The superuser, typically called root, is a privileged user account that bypasses normal Linux permission restrictions. It has a user ID (UID) of 0 and can read, write, or execute any file and run any command without being subject to standard file permissions or security restrictions.
Most Linux systems restrict normal users from dangerous operations—like modifying system configuration files or installing software—by denying them the necessary permissions. The superuser account exists to allow system administrators to perform these critical tasks. For example, only root can bind to network ports below 1024 or modify the contents of /etc/passwd.
However, using the superuser account for routine tasks is risky because a single mistake or malicious command can damage the entire system. Best practice is to use a normal user account and escalate privileges only when needed, typically via sudo, which allows authorized users to run specific commands with superuser privileges.