Analysis: The design of teaching system can generally be summarized into three levels, that is, the level centered on "products", such as the design and development of online courses, and the design of media, materials, teaching packages and online teaching systems needed in teaching as products; The "classroom"-centered level, such as information-based teaching plan design, is to design a teaching system for a class of students according to the requirements of the syllabus under the condition of fixed teaching facilities and teaching resources; System-centered level, such as the formulation of enterprise training plan, usually includes the determination of system objectives, the establishment, trial implementation, evaluation and modification of target plan.