iCloud: Calendar sharing in iCloud
You can share calendars publicly and privately using Calendar on iCloud.com.
In the sidebar, a shared calendar has a darkened Share button .
Public calendars can be shared with anyone using the Calendar app on an iOS device or Mac; Microsoft Outlook on a Windows computer; or any other app that supports the iCalendar file format. Only the calendar’s owner can make changes to a public calendar.
Private calendars can be shared with iCloud users using Calendar on iCloud.com, the Calendar app on an iOS device or Mac, or Microsoft Outlook on a Windows computer.
For private calendars, you can assign two types of access privileges to the people you invite:
View & Edit: The invitee can create, edit, and delete events, and track invitation responses.
Only one person can edit a shared calendar at a time.
View Only: The invitee can only change their own view settings.
Note: Only a calendar’s owner can share it.
If you stop using iCloud, any shared calendars you created become unavailable; all participants automatically receive an email notifying them that the calendar is no longer shared.