SELECT * FROM USER: infrastructure and socio-technical representation.

As use of, and experiences with, social media continue to grow, the systems of representation that underlie their use become increasingly influential. In this paper, we present results from empirical studies of two online communities-Facebook and craigslist Missed Connections-that highlight the ways in which this underlying infrastructure and the user practices on these sites are inherently intertwined. We make particular use of a framework first introduced by Agre that focuses on the influence of eight underlying features of computing practice: ontology, standards, instrumentation, authentication, interpretation, selection, bias, and performance. The results of this analysis indicate how representational systems do more than simply represent the physical world; they are deeply intertwined with the social and material practices of everyday life.