Link	Shared Google Calendar	Google Calendar invites
Others get notification emails	Yes If added to the event explicitly	Yes
Others can edit event	Yes	Yes Only if event creator checks "Guests can modify event"
Custom colors	Yes Per calendar
Each event appears once	No Event appears both in the shared and in the personal calendar if invited. Removal from personal calendar marks as "No" in shared calendar.	Yes
Others get event change notifications	Yes If added to the event explicitly	Yes
Event creator notified of RSVPs	Yes If configured via Reminders & Notifications settings	Yes
Inform others of unavailable times	Yes Mark block as busy and just don't invite others	No Unless bogus-inviting others to unavailable times as an event
Retrospective of events together	Yes Uncheck other calendars	- Search / filtering?
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