The very notion of community in an online context can begin a hot debate. Those who would keep the term ‘community’ for the imagined ideal of cooperation and joint sharing of land, resources, and goals ask: How can community exist without physical co-location and a geographic touchstone? How can the leanness of computer-mediated communication support the richness inherent in a community? This article revisits the debate about community and online community, and offers a means of conceptualizing and investigating online community using a social network perspective that frees it from its former geographical constraints. It begins with a look at the challenges to community that have fed into arguments against online community, and with a section on the discovery of community online. The article then addresses the case for a network view of community, starting with how the social network approach has been applied to offline communities and how this lays the groundwork for unbundling community from face-to-face interaction and geographic co-location. Following a brief section on the basics of social-network terminology, it returns to the main topic of community, with a focus on the network-level aspects of community, showing how patterns of interpersonal ties can build a network with outcomes greater than the sum of the pairwise connections. The final sections explore variants on the theme of community, first by revisiting the online and offline dichotomy and addressing the advantages, and indeed the inevitability, of considering community from both online and offline sides.