It is collapsible. Only the time is shown if the lock has the key pointing to the right (horizontally). Panes, indicating various modes and controls, appeared when the lock was clicked and the key was pointing down (vertically). Alarm Clock collapsed once again when the lock was clicked.
The Alarm Clock had three main panes:
- The time pane (represented by the analogue clock) was where the time could be set. Note that the Alarm Clock did not support automated DST time adjustments.
- The date pane (represented by the calendar, where a calendar page representing Day 1 or the 1st of the month is being torn away, revealing Day 2 behind) was where the date could be adjusted.
- The alarm pane (represented by an alarm clock that's about to go off) was where the very confusing alarm could be set.
The alarm was the most confusing aspect of Alarm Clock. To set the alarm, the time had to be set inside the alarm pane, and a switch (to the left side of the window) had to be clicked/flipped so that the upper part had a tiny square showing (meaning that the alarm was set and active). To switch it off, the switch had to be clocked so that the tiny square was shown in the lower part (meaning that the alarm was no longer activated).
When the alarm "went off", the system beep sounded once -- and once only. The Apple menu would flash between the Apple logo and the icon of an alarm clock going off. This would go on forever until the alarm was switched off (by clicking the alarm switch inside the alarm pane of Alarm Clock).