Social media are now established as an important aspect of contemporary education. We live in times where social media applications such as Facebook, Twitter, Tumblr and Snapchat are mainstream educational tools; where most new educational technologies claim to have a `social' element; and it increasingly makes no sense to distinguish between learning `online' and `offline'. It studies users' experiences and views of social media; addresses questions of equality and diversity concerning who is doing what with social media; examines how the use of social media applications sits alongside pre-existing cultures and structures of schooling; and brings to light the unintended and unexpected results of social media in education. Altogether, this collection of writing provides a nuanced and interesting discussion of the realities of social media use across different aspects of education. This book was originally published as a special issue of Learning, Media and Technology.