This book explores the ways that scholars, journalists, politicians, and citizens conceive of "the public" or "public life," and how those entities are defined and invented. For decades, scholars have used the metaphors of spheres, systems, webs, or networks to talk about, describe, and map various practices. This volume proposes a new metaphor-modalities-to suggest that publics are forever in flux, and much more fluid and dynamic than the static models of systems or spheres would indicate-especially in the digital age, where various publics rapidly evolve and dissipate.