1. Definition of distance education: Distance education refers to the education of transferring courses to one or more students outside the campus. Modern distance education refers to the education of transmitting courses outside campus through audio, video (live or video) and computer technology including real-time and non-real-time The history of distance education in the world can be traced back to the s of this century. With the emergence of advanced information technology, especially the Internet, the characteristics of distance education have undergone profound changes. 2. Development of distance education: At the beginning and middle of this century, distance education technologies (such as printers, radios and televisions) were characterized by one-way transmission. During this period, distance education technology is mainly used to transmit information from teachers to students. This mode of communication failed to play the role of communication between students, and only achieved limited communication between students. Terrain generation and transmission technology also has time constraints (for example, students listen to the radio and watch TV programs in advance). The second generation technology appeared in 2000, which greatly improved the dependence of the first generation technology on time. With the emergence of video recorders and cable TV, the spread of distance education courses is not limited by time. The recorded videos of course contents are sent to students so that they can watch them at any time. However, in other respects, this generation of distance education technology is not much different from the previous generation: there is still little communication between students and between teachers and students. In the mid-1990s, distance education began to use personal computer technology, and soon, a two-way video conference system appeared. Compared with before, the third generation distance education technology enables teachers to send a lot of more complicated information to students, and enables students and teachers to communicate with bulletin board system through e-mail, chat rooms. Computer-aided instruction. Computer simulation and other electronic resources through computer disks, CDs and the Internet further show the characteristics of this generation of distance education. The fourth generation distance education technology is more advanced. The communication between students and between teachers and students has been strengthened. The number and types of information exchange have increased significantly, and the time required for work has become shorter. This reduces the dependence of distance education on time and space and makes it possible to realize a real virtual university. Modern distance education integrates the second, third and fourth generation technologies. 3. Distance education in China: The development of distance education in China has experienced three generations: the first generation is correspondence education. This method has trained many talents for our country; The second generation is radio and television education, which rose in 1998. This way of distance education in China and CCTV are world-famous. In 1990s, with the development of information and network technology, modern distance education based on information and network technology rose in China.