Marking an appointment as private

You can mark appointments as private to hide details of the appointment on your calendar.  A small lock icon, ,  appears next to the message on your calendar to show that this is a private appointment.  Calendars that are shared with others show the appointment on your calendar but do not show any details.   

By default when you create or receive an appointment, it is marked as Public. If you always want appointments you create and receive to be marked as Private, you can modify your Calendar Preferences Default appointment visibility to Private.

If you set the default to Private, all incoming calendar invites are marked as private on your calendar.

If your default is Public and you receive an invite that is marked private by the organizer, the appointment is marked as private on your calendar.