The differences between computer-mediated and in-person learning are of increasing interest to educators, both with the rise of fully online education offerings and the move to 'blended learning' when teachers use computer-mediated learning to supplement and extend classroom activities. This paper offers a narrative history of the world's first computer learning system, PLATO, developed at the University of Illinois between 1959 and 1976. The PLATO experience prompted discussions regarding the nature of e-learning among the developers that have since become a ubiquitous part of our educational discourse. While the technical story of PLATO and its place in the development of cyberculture has been told, the educational story has not. This paper discusses the ways in which educators using PLATO gradually discovered that their teaching and their students' learning could be different. It analyses the implications of these insights for the emergence of e-learning pedagogies in subsequent decades.