moca is an open source learning management system that allows for e-learning on cloud platforms like Windows Azure. It supports various learning and teaching styles for small and large learning communities. Some key advantages of using a cloud-based system include no hardware worries, lower costs, high availability, scalability, and reduced IT costs. The system uses SQL Azure for storage and has a modular structure. It is one of the most widely used open source LMS with over 50,000 learning communities and 9 million users globally. Courses can include various resources like text, images, videos and activities like assignments, quizzes, forums, chats and wikis to encourage interaction. Detailed analytics of student performance are also available.