Of the many factors affecting our lives today, the ever-changing landscape of education is at the forefront. Learning is a complex behavior which involves cognitive, affective, and psychomotor domains. While pedagogy is the art and science of teaching children, andragogy is the art and science of teaching adults. The term pedagogy came into use in the seventh century. It wasn't until the 19th and 20th centuries that what we know as traditional learning theories—behaviorism, humanism, cognitivism, social cognitivism, and constructivism—were recognized. They were derived from the investigative tools of theorists—Pavlov, Skinner, Piaget, Freud, Maslow, Rogers, and Thorndike—to understand the nature of learning. In 1970, Malcolm Knowles promoted andragogy as a model of assumption that serves as a basis for an emergent theory. Today, the way of differentiating adult learners from children learners is through the process of andragogy.