Public debates today are shaped by the hashtag. The simple # sign is now used so widely that it is easy to overlook the fundamental effects that it has had in the structuring of public debate. With its help, statements are bundled together and discourse is organized and amplified around common buzzwords. This method enables us to navigate more easily the huge volume of online utterances and it generates better visibility for collective arguments, but it also increases the risk of leveling statements and extinguishing difference. The #MeToo debate, for example, has demonstrated this problem of demarcation in hashtag-centered debates very clearly. This short book traces the young and spectacular career of the humble hashtag. It follows the history of the # sign, situating it within the context of earlier methods of keywording and indexing and documenting its use by Twitter and Instagram, and then examines the most prominent contemporary domains of the sign in sociopolitical activism and in marketing - two apparently very different fields which are united in their passion for the hashtag. Theory of the Hashtag shines a bright light on a small but pervasive feature of our contemporary digital culture and shows how it is surreptitiously shaping the public sphere.

It is a short book about the most prominent sign of our times.