During the last decade the world of education has been swept by a series of philosophical and technological developments whose promise can no longer be ignored. One of these which emerged from the learning psychologist's laboratory and has already given birth to a new industry is programmed instruction, more popularly thought of as teaching by machine, but often available in book form.
The theoretical core for this instructional method is the now well-established principle that the efficiency and effectiveness of learning can be increased if a learning task is broken into logical and sequential steps and the student informed promptly at the end of each step whether he has learned what he is supposed to learn. The small steps to which the psychologist refers are not week-by-week or day-by-day efforts, but moment-by-moment learning activities. The virtual impossibility of such an exchange between teacher and student, even in a tutorial setting,