Although unix is a complex system, most users get along fine using only a small fraction of the commands available. Unix also has many shortcuts available to make things easier to remember and type. Case sensitivity One of the most important things to remember about UNIX commands is that they are case sensitive, which means the system distinguishes between uppercase and lowercase letters.
Command line Enter the commands described here at the command line.
The command line is one way to interact with the computer. If you login to Unity by telnet or modem, the command line is your only interface to Unity. If you log in from a UNIX-based workstation running an X Window System, you can access Unity with numerous windows with which to run applications. There is no name or machine name unless you alter the way the system displays the prompt. Argument is usually the file or directory upon which the command operates.