Affect and Social Media is an edited collection of twenty bite sized articles by leading scholars from across disciplinary boundaries. It is comprised of four distinct but related sections which are interspersed with artistic illustrations, depicting the affectivities that flow through social media. The term ’;affect’ denotes a rather slippery concept that is not as easily caught as for example ’;emotion’ or ’;feeling’. Quite often it denotes a more than or an excess to that which is felt in the human body or indexed through cultural grids of meaning. It can exist in ways which defy expectations, conventions, and representations. It is often understood as that which is vital to the emergence of the new and hence socio-cultural revolution. As life shifts ever more on-line, we find ourselves caught up in the affective flows of computer mediated practices into an ever expanding and indeterminate horizon. This compilation of articles that were initially presented at an international conference in East London, were selected on the basis of their ability to depict and conceptualise these radical movements of sociality.