The user interface of the Elan Programming Environment is by itself rather simple, but its description gets rather complicated because of the many ways of interaction with the user. For concise description, we will denote the ``return'' or ``enter'' key by <RET> and the ``delete'' or ``rubout'' key by <DEL>, the ``backspace'' key by <DEL LEFT>. The <BREAK> is a special key to notify the Elan Programming Environment to stop whatever it is doing. Its realization may well be different for the various implementations (CNTL-C, BREAK-key, special buttons, etc.; read the documentation which is distributed on the floppy disc with the software). In screen output, the cursor is depicted as .