1. The first generation was correspondence education, which trained many talents for the country, but correspondence education has great limitations.
2. The second generation is radio and television education, which rose in 1980s. This mode of distance education in China and CCTV are world-famous.
In 1990s, with the development of information and network technology, the third generation of modern distance education based on information and network technology came into being. At the end of 1994, under the auspices of the State Education Commission at that time, the CER demonstration project in China was jointly undertaken by 10 universities including Tsinghua University. This is the first public computer network in China that adopts TCP/IP protocol.