Social media would not have been possible without the advances in the field of human-computer interaction (HCI). It was laying the basis for interactive systems early on when computers became personal, focused on how humans would not only work collaboratively, but how people could connect and socialize beyond boarders, be it organizational or geographical. Social media has changed society dramatically. From a systemic change perspective, the interplay between people and technology was moving from a single user interacting with a system, to groups of users interacting with a variety of connected systems – impacting companies, organizations, communities and societies. This chapter gives a brief and simplified overview on the history of social media, followed by a systemic change oriented analysis how social media is changing the way people live, how they socialize and make friends. It then focusses on how societies change on national and international level using as an example the recent twitter activities of Kpop fans during the US presidential election campaign showing how new organizations and groups of people start to interact in ways that were unimaginable 15 years ago.