Over the last decade the daily experience of adolescents has been transformed by developments in electronic media, including the computer, the Internet, and cell phones. Relative rarities only a generation ago, they are the daily tools of communication, information, and amusement for a majority of adolescents. Beyond access, content and capabilities have exploded. Even television, long a ubiquitous presence in American households, has seen content change and has grown dramatically. Parents, policymakers, and researchers acknowledge the power of this transformation, and have become increasingly concerned both about the potential hazards they present to the health and well-being of young users, and that unequal access to their perceived benefits may limit long-term prospects (the so-called "digital divide"). In this brief, we provide a concise overview of research relating electronic media to the health, social development, and educational outcomes of adolescents. We also present data describing trends and inequalities in access to electronic media as well as the time adolescents spend and the activities they engage in through these media. We conclude with a brief discussion of the implications for policy, research, and data collection. (Contains 7 figures.)