Communication is the exchange of information between people. It is the way in which people make contact with each other. Nonverbal communication involves body movements and concealed messages. Communication skills help people exert control over what they want to do. When people communicate, they tend to concentrate on the words that are spoken. Oral language, therefore, becomes an important part of communication. To be in tune with the whole message, a listener should be skilled in trilevel communication. Communication may be categorized into two major groups, informal or formal. Small talk is the friendly exchange of personal or impersonal information. Social conversation usually involves superficial, passing remarks. Light communication is one of the different levels of social interaction important to the psychological method of treatment called Reality Therapy. Catharsis involves emotion-filled, intense communication. The words are spoken with sincerity. After a period of cathartic communication, the speaker feels a cleansing or emptying effect.