The key new feature is the introduction of different Clubs.
Windenburg is described as a European-inspired World hub that focuses on giving the player more social interaction activities.
'Get Together' introduces the new locale Windenburg and more social partying activities.
'The Sims 4' currently has had a lot of minor content packs but only one expansion, 'Get to Work.' That is about to change with the arrival of the 'Get Together' DLC which is scheduled to be released this November.
