The document discusses Malcolm Knowles and his theories of adult learning, or andragogy. Knowles introduced the concept of andragogy to describe how adults learn differently than children, with adult learners being self-directed, goal-oriented, and drawing on life experiences. The document also outlines some key characteristics of adult learners and factors that motivate adult learning, such as social relationships, personal advancement, and cognitive interest. Barriers to adult learning are also discussed, including lack of time, money, and confidence.