Research and debates about the significance and role of social media for democracy – especially in regard to promoting citizens’ participation in politics – continues with much intensity. The discussions are often either optimistic or pessimistic in character, and research evidence can seemingly be found for both sides. Other voices assert that we should be dispassionate and realistic in these matters. This text shares that view, but also points out that it is not always easy to be realistic: to understand the impact of social media we must look at them in their social contexts, and this can become complicated. Yet it is our best way forward. This text seeks to shed light on the democratic potential and limitations of social media by taking a contextual perspective. This will include understanding how social media are embedded in our everyday lives, probing the character of mediated political participation, and illuminating some basic technical and social attributes that shape the character of social media.