Teaching Machine, a mechanical or electronic device for self-teaching. The teaching machine presents the learner with a sequence of questions, problems, or instructions. The learner responds to each item, typically by pressing one of several buttons. Teaching machines have been used in school systems and job-training programs.

A teaching machine presents information in a carefully planned manner, generally in small steps that can be mastered easily. Mistakes are revealed immediately so the student or trainee does not learn something that is incorrect. Subject matter presented in this way is called a program, or programmed material.

Experimentation in mechanized teaching was begun in the 19th century. Several kinds of devices were in use by the time of World War II. In the mid-1950's, the psychologist B. F. Skinner devised programmed materials that led to the development of several kinds of teaching machines. By the early 1980's, most of these machines had been replaced by computers. The use of computers for self-teaching is known as computer-assisted instruction, or CAI.