"Online course is a course based on Web, that is, a course learned through WWW browser on the Internet" (defined by learning tools and means);

Definition 2:

"Network course is a course that embodies modern educational thought and modern teaching and learning theory" (defined on the basis of guiding ideology and theory);

Definition 3:

"Online courses are resource-based learning, situational learning and collaborative learning" (defined from the three characteristics involved in the constructivist learning environment);

Definition 4:

"Web-based course refers to a course characterized by interactivity, sharing, openness, cooperation and autonomy in the learning process" (defined from the characteristics of the learning process);

The above four definitions of online courses have their own basis and rationality, and their influence and application range are large; However, because they only consider one aspect of the characteristics of online courses, they are still one-sided.