Mac-Terminal.com

An introduction of the Terminal for Mac OS X

Mac OS X Terminal - System

System information - Display advanced system info about your Mac
Sudo - Execute commands as a super user
Processes - Manage processes, PID's on your Mac
Crontab - Scheduler
Customize your Mac - advanced configuration
Users - Manage user accounts

Sudo - how to use it in Mac OS X

Syntax: sudo <Other command>

Explanation: Sometimes you might not be able to perform a certain command or task from the Terminal. When that occurs, try adding "sudo" before the rest of the command you're trying to execute.
Sudo stands for superuser do and means that you want to execute the following command as a superuser or Administrator. When using sudo you might be asked to enter the system root password.

Example

sudo rm protected_file.zip	Tries to remove the file "protected_file.zip" with sudo.
sudo chmod 0775 protected_file.zip	Tries to change permissions of the file "protected_file.zip" with sudo.