when the window is selected.
If the window is the main window of a running application, the
application usually will terminate.
Closing a window removes it from the screen.
To close a window, select Close from the window
menu or press the accelerator
when the window is selected.
If the window is the main window of a running application, the
application usually will terminate.
Not all applications respond gracefully to this type of termination. Some applications may force you to perform additional steps to terminate if you close its main window. If an application uses multiple independent primary windows, selecting Close may either close just that window or cause the application to exit.