Nonverbal communication is communication without words, for example, communicating with what is often called "body language". Humans communicate ideas by nonverbal means naturally as eye-contact and hand gestures all form a part of conversation. Effective wordless communication, however, is another matter. Communicating effectively without words is a skill that can be mastered. Nonverbal communication courses can be used to enhance verbal communication, whereas when used improperly it can invalidate verbal communication and/or make an audience skeptical.
An introduction to nonverbal communication covers the basics of the following areas:
The space around people affects their moods. You see this in such terms as "mood lighting". Certain colors of paint on a wall may also affect how a room influences the way people feel while inside it. Speakers who want to exert a certain kind of influence over their audience will often speak from a platform or pulpit because being above the audience confers authority and subconsciously makes the audience more willing to receive their message. Arranging furniture and decorating a room in a particular style can be viewed as a form of nonverbal communication. Wordless communication with environmental conditions is covered in the textbook Meaning of the Built Environment: A Non-Verbal Communication Approach by Amos Rapoport.
This is a word for body language. Body language refers to the fact that such things as body posture and movements communicate certain things about people. How a person moves often correlates with what they are communicating verbally, and may also communicate things that they are not saying. Learning to interpret body language is an important part of nonverbal communication. Body language is a broad term used to cover such areas as gestures used while talking, physical characteristics (race, height, weight etc.) and the ability or inability to make eye-contact. A good textbook on kinesics is Kinesics and Context: Essays on Body Motion Communication by Ray, L. Birdwhistell.
How someone dresses can communicate certain messages and thus is also a means of nonverbal communication. For example: a man in a uniform tells certain things about his job, in some cases his rank, as well as the people he works for. The purpose of a uniform is nonverbal communication, as is the purpose of such things as things as badges and national flags. In social settings some forms of dress can indicate a desire for sexual activity, or the lack of such a desire. A good textbook on this is Casual Power:: How to Power Up Your Nonverbal Communication &amp; Dress Down for Success by Sherry Maysonave.
This is how people communicate with their voices in ways other than with words. A person can communicate anger or other emotions with their tone of voice, which is separate from what they are saying. The inflection in a voice can alter the meaning of the words being said. Complete interpretation of what a person is saying requires the ability to grasp the cues in their tones of speech as well. Even though this is speech it also falls into the category of nonverbal communication. Paralanguage is described in Paralanguage and Kinesics: Nonverbal Communication by Mary Ritchie Key.
Nonverbal cues differ according to culture. Certain behaviors that may indicate one thing in one place may be understood another way somewhere else. A course in nonverbal communication may also help people to understand other cultures.