Malcolm Knowles developed the theory of andragogy, which focuses on adult learning principles rather than pedagogy which is based on teaching children. Knowles believed that adults learn best when they have control over their learning. He identified key assumptions about adult learners including that they are self-directed, draw on life experiences, are problem-centered, and want learning to be immediately applicable. Knowles developed principles for adult education based on involving learners in planning, using experiences for learning activities, focusing on relevance, and taking a problem-centered approach rather than content-driven.