When an alarm goes off for a particular event or appointment, a window will come up on your screen (and a sound will go off if you’ve selected one). If you wish to temporarily have the alarm go away, click the “Snooze” button. This will reset the alarm for 15 minutes later. If you click the “OK” button, the alarm will not come back (unless it’s a yearly event, if so, the alarm will reset itself for one year later).