Group dating: an activity shared by two or more couples.
Blind date: a date where the participants have not met each other personally before (although may have seen each other's pictures); usually set up by a third party or an internet dating service.
Long Distance / Holidating: due to a long distance relationship, dating only when one, or both parties are on holiday or a big vacation and are together during that time period.
Dating exclusively: when two people forming the couple expect each partner not to go out on dates with third parties.