Adult learning refers to learning beyond compulsory schooling that can take place in formal education programs, on-the-job training, or through self-directed learning. Andragogy is the method and practice of teaching adult learners, in contrast to pedagogy which focuses on teaching children. Some key aspects of andragogy are that it emphasizes self-directed, problem-based and collaborative learning rather than didactic teaching methods. Adult learners learn best when the instruction is relevant, interactive, practical, and respects their experience.