What is per-event RSVP?

Per-Event RSVP means you can invite some of your guests to some events, and others to other events.

E.g.

Tom is invited to the ceremony only so can not see the reception details
John and Jill are invited to the ceremony and reception, but their kids are only invited to the reception
Parents of the couple are invited to all events

You can also create events that do not require RSVP, and events that do require RSVP, but are still shown to everyone regardless.