Ticketing:-  This is  best suited for  Entertainement, sports  or events of  similar nature. Where the nomenclature is used such as Buy Ticket, Issue  Ticket, Ticket Details etc.    
Registration:- This nomenclature is best suited for Business events,  Conferences, workshops   seminars etc. In this type , the  buttons or the wording changes to Register,  Issue Pass, close Registration and so on.    
RSVP:-
 This is a type of event where  you just want to count the confirmation of attendees who are committed to  attend your event.  This is mostly a  free event where no payment is needed to be paid by the attendees.      

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