In the design and development of distance education courses, interactivity is an important factor that must be considered. Many advanced technologies have been used to strengthen interaction, so as to overcome the loneliness that students are prone to in distance learning. Berge, a senior expert in network teaching research, gave a broad definition of interaction in distance teaching environment: "Interaction is a two-way communication between two or more individuals in a certain learning environment, and its purpose is to promote the completion of learning tasks or the construction of interpersonal relationships. Therefore, interaction is a way for teachers and students to receive information feedback and adapt to learning activities. "

There are two types of interactive activities in distance network teaching, namely interpersonal interaction and teaching interaction. These two interactive activities also exist in the traditional face-to-face teaching. In online teaching, interpersonal interaction can be conducted through e-mail, voice mail, mailing lists, newsgroups, chat rooms, bulletin board system, online meetings or other two-way communication media. Teaching interaction is carried out through interactive tools such as instant feedback, question and answer, rhythm control and frequency control.

Today, distance network teaching staff can get more media technical support. Online course exchange system has been widely used in online teaching. The following is an introduction to the interactive media often used in distance online course learning.

1. email

E-mail is used to convey personal information in online learning. As a tool of interpersonal communication, it allows learners and teachers to communicate one-on-one. Using e-mail, teachers can communicate with learners, and learners can also communicate with each other. Similarly, using e-mail, teachers or other learners can get feedback, thus helping learners in their learning activities. Some distance courses can also provide a voice mail system, which allows learners to communicate with others through voice instead of text mail.

2. Online discussion groups

Online discussion groups allow learners to talk about topics of common interest with others. This discussion environment includes newsgroups and mailing lists. The mailing list is actually a large online discussion group, which can send e-mail information to users who have subscribed to this email content. Newsgroups are similar, but newsgroups are limited to a meeting instead of sending information to users. In other words, newsgroups need users to actively participate in discussions. Mailing lists only passively accept information from personal accounts. Bulletin board system (BBS) can also involve all learners, no matter when and where they surf the Internet.

3. Online resources

Learners can use online search engines to collect relevant information to assist their learning activities. Some websites provide a collection of some kind of network resources. This resource is essentially some address information. Like argus.

Clearing house and Eric

Clearinghouse, two websites, can be said to be no less than any encyclopedia printed on paper. In addition, e-magazines also provide convenient access and instant learning resources for distance learners.

4. CDs

The capacity of CD is very large, and it can store a lot of video, audio, animation and interactive multimedia information. Many online courses are provided in the form of CD-ROM, which integrates many interactive multimedia materials. CD-ROM not only provides well-structured and well-designed courses, but also integrates words, images, pictures, sounds and animations to achieve synchronous reproduction. In the learning process, the computer of the distance learner is disconnected from the network, rather than through the online environment, which can save the cost of establishing the network interconnection channel. Therefore, CD-ROM provides a cheap and effective tool for distance learners.

5. Online courseware

A large number of online course management tools, such as Blackboard, WebCT, LearingSpace, TopClass, WebCourse and FirstClass, can help course designers or teaching staff to create a complex online learning environment, including teaching staff management, course design and student evaluation. For example, in the online course design environment of Blackboard and WebCT, all interaction activities with online courseware are conducted through web browsers, and both provide synchronous interaction and asynchronous interaction between teachers and students.