A Listener is created automatically when you start Common LispWorks. You can also create a Listener yourself by choosing
Window > Tools > Listener
or press 
in the LispWorks toolbar.
In the Listener view, the main area of the Listener contains a prompt in its top left-hand corner.
Rather like the other types of command line prompt, this prompt helps you identify the point in the Listener at which anything you type is evaluated. It may also contain other useful information, by default this is the current package and the current number in the command history list. If your Listener is in the debugger, as Listener, the prompt also contains a colon followed by an integer indicating how many debugger levels have been entered.
Throughout this chapter, the prompt is shown in pieces of example code as PROMPT > .
You can click the Output tab to display the output view of the Listener; this view displays any output that is created by the Listener, or any child processes created from the Listener..
To familiarize yourself with the Listener, follow the instructions in the rest of this chapter, which forms a short lesson. Note that, depending on the nature of the image you are using, and the configuration that the image has been saved with, the messages displayed by Lisp may be different to those shown here.