PLATO (Programmed Logic for Automatic Teaching Operations) was the first generalized computer-assisted instruction system. Starting in 1960, it ran on the University of Illinois' ILLIAC I computer. By the late 1970s, it supported several thousand graphics terminals distributed worldwide, running on nearly a dozen different networked mainframe computers. Many modern concepts in multi-user computing were developed on PLATO, including forums, message boards, online testing, e-mail, chat rooms, picture languages, instant messaging, remote screen sharing, and multiplayer games.
PLATO was designed and built by the University of Illinois and functioned for four decades, offering coursework (elementary through university) to UIUC students, local schools, and other universities. Courses were taught in a range of subjects, including Latin, chemistry, education and primary mathematics. The system included a number of features useful for pedagogy, including text overlaying graphics, contextual assessment of free-text answers, depending on the inclusion of keywords, and feedback designed to respond to alternative answers.
Rights to market PLATO as a commercial product were licensed by Control Data Corporation (CDC), the manufacturer on whose mainframe computers the PLATO IV system was built. CDC President William Norris planned to make PLATO a force in the computer world, but found that marketing the system was not as easy as hoped. PLATO nevertheless built a strong following in certain markets, and the last production PLATO system did not shut down until 2006, coincidentally just a month after Norris died.
Before the 1944 G.I. Bill that provided free college education to World War II veterans, higher education was limited to a minority of the US population, though only 9% of the population was in the military. The trend towards greater enrollment was notable by the early 1950s, and the problem of providing instruction for the many new students was a serious concern to university administrators. To wit, if computerized automation increased factory production, it could do the same for academic instruction.