Two-way communication is a form of transmission in which both parties involved transmit information. Common forms of two-way communication are:

In-person communication

Telephone conversations

Amateur, CB or FRS radio contacts

Computer networks . See back-channel.

Chatrooms and Instant Messaging

Two-way communication is the opposite of broadcasting.

Nonverbal communication (NVC) is usually understood as the process of communication through sending and receiving wordless messages. Such messages can be communicated through gesture; body language or posture; facial expression and eye contact; object communication such as clothing, hairstyles or even architecture; symbols and infographics; prosodic features of speech such as intonation and stress and other paralinguistic features of speech such as voice quality, emotion and speaking style.

http://home1.fvcc.edu/~rhalvers/Roadblocks%20to%20communication.htm

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