Start time — These fields define the start date and time of the event. You may type the date directly in the date field, or use the pop-up calendar to select a date. Click on the small button at the right of the field to bring up the calendar.
You may type the time directly in the time field, or use the combo box to select an appropriate time.
End time — These fields define the end date and time of the event.
Duration — specifies the amount of time the event lasts. Changing the duration changes the end time of the event relative to the start time.
All day event — Select this option to make the event that lasts for one day or more.
Recurrence... — This button allows you to setup a recurrence for the event.
Modify the series... — This button allows you to modify settings of the series of the recurring event, instead of a single occurrence of the event.
Notify — Select this option to have the event remind you before its start time.
Undo changes — This button allows you to restore the modified occurrence of the recurring event to its original properties.