This document provides an overview of andragogy, the study of adult education. It discusses key concepts in andragogy including that it focuses on "man leading" or self-directed learning as adults have accumulated life experiences. The document contrasts andragogy with earlier subject-centric models of education and outlines principles of andragogy including creating a supportive environment, collaborative learning, and dealing with obstacles to learning. It also discusses the role of teachers in balancing lecture, discussion and visual methods to operationalize abstract concepts and build critical thinking.