The user screen displays messages sent to the user from a running program. You cannot use this screen to change information.
User messages are controlled using the MESSAGE instruction in your program. Each time the MESSAGE instruction is used, one line containing up to and including 23 characters, is written to the user screen.
A maximum of nine message lines can be displayed. If more than nine message lines are used, the tenth line is added to the bottom of the screen and the top line scrolls off.
For KAREL programs, user messages are controlled by using the write statement in your program.