A window can run on a remote system. This means that the server controls the actual hardware used for input and output, and the clients make requests of the server. This allows client programs to be independent of the hardware. In X terminology, the display server is called either the server or the display. The actual hardware is called the screen.
Clients are the application programs that make requests of the display server.
AIXwindows Window Manager is an example of a client. The command line interface is also known as the shell . This interface is character-based. The screen displays a system prompt, and the commands you type from the keyboard appear next to the prompt. If your screen looks like the AIX Common Desktop Environment Startup illustration , you are in the CDE graphical interface.