Why the English use the RSVP?

The English use RSVP, derived from the French phrase "Répondez s'il vous plaît," meaning "Please respond," to indicate that a reply is requested for invitations, particularly for formal events. This practice helps hosts plan accordingly by knowing how many guests will attend. It reflects etiquette and consideration for both the host and attendees. Using RSVP shows respect for the event and helps manage expectations for the occasion.