RSVP cards are small cards included with invitations to events, such as weddings or parties. They allow guests to confirm their attendance by providing a simple way to respond. Typically, these cards include options for guests to indicate whether they will attend, along with a space for their name. The term "RSVP" comes from the French phrase "Répondez s'il vous plaît," meaning "Please respond." By sending back the RSVP card, hosts can better plan for the event, including seating arrangements and catering needs, based on the number of attendees.