1. Communication is a process of transmitting and feeding back thoughts and feelings between people and between people and groups, so as to achieve ideological consistency and emotional smoothness.

2. Communications are classified by structure.

The basic structure of communication includes three aspects: information, feedback and channels. Without either party, communication cannot be completed. According to the specific structure, communication can be divided into informal communication network and formal communication network. Through the study of "gossip", it is found that informal communication networks mainly have typical forms such as cluster, gossip and chance; Regular communication networks have many forms, such as chain, wheel, omni-channel, Y-type and so on.

3. Communication is classified according to the direction of information flow: communication can be divided into upward communication, parallel communication and downward communication.

4. Communication is classified according to communication methods.

According to communication methods, communication can be divided into verbal communication and nonverbal communication. Verbal communication includes oral communication and written communication, while non-verbal communication includes pronunciation and intonation (such as music) and body movements (such as gestures, dance, martial arts, sports, etc.). The most effective communication is the combination of verbal communication and nonverbal communication.