Programed instruction applies what is known about learning to educational psychology. The success of programed learning is determined by the material used and by the construction of this material. In order to construct effective learning sequences, the behavioral end products of instruction must be specified clearly and precisely. The subject being taught must be presented in a carefully arranged series of steps, called frames. The sequence as a whole, not the features of a single frame, guides the learner by encouraging the repetition of an increasingly more precise response in appropriate situations. Learning is fostered by reinforcement and "reward," in conjunction with appropriate cuing and immediate feedback. There are two types of programs, linear and branching, with intrinsic programs and multi-track programs being forms of branching. Current programs employ several different response modes, among which multiple response and constructed response are the most widely used. (OH)