Moodle is an open-source e-learning software and course management system (CMS) that supports various operating systems and allows for a hybrid approach to learning. It features a simple user interface, and incorporates a social constructivism educational philosophy, providing tools for sharing materials, engaging discussions, quizzes, and managing assignments. Moodle's architecture includes components for static and dynamic content, various course formats, and management tools to ensure a smooth online learning experience.