Superuser or Root

• Priviliged account, with username root, with unrestricted access to files and commands
• The UID of root is 0 (zero)
• Any user with UID 0 acts like root
• Operations restricted to root only
• Mounting and unmounting filesystems
• Changing the root directory of a process with chroot
• Creating device files
• Setting the system clock
• Changing file ownership (on BSD systems)
• Raising or lowering resource usage limits
• Increasing or decreasing the priority of a process
• Setting the system's hostname
• Configuring network interfaces
• Shutting down the system
• Two ways to become root
1. Log in directly as root
2. Use the command su while logged in a non-privileged account
• Become superuser only when absolutely necessary
• Unlimited access to everything in the system can accidently destroy the system
• Do all your routine work in a non-privileged mode