The word open is receiving a lot of attention in education circles. Openness in higher education has been discussed recently by writers in the Chronicle of Higher Education, the New York Times, EDUCAUSE Review, and EQ, among other publications. In January 2010, The Horizon Report, produced by the New Media Consortium (NMC) and the EDUCAUSE Learning Initiative (ELI), declared that open content will “reach mainstream use” in higher education within the next twelve months. But what does that mean? What is this open we keep hearing about?