This document discusses programmed instruction and teaching machines. It notes that programmed instruction is an instructional strategy aimed at modifying learner behavior, not a test or replacement for teachers. It requires creativity to break content into small, logical steps and provide feedback to students as they learn at their own pace. Different types of programming include linear and branched structures. Teaching machines were constructed to deliver programmed instruction without a teacher and allow students to learn through doing and self-assessment. Cybernetics, the science of communication and control in animals and machines, informed the development of these systems.