Non-verbal communication refers to communicating without words through facial expressions, body language, tone of voice, and other cues. Studies show that 93% of interpersonal communication is non-verbal. Non-verbal cues can play five roles: repetition, contradiction, substitution, complementing, and accenting messages. Types of non-verbal communication include body language, clothing/artifacts, voice/paralanguage, space/proxemics, color, time/chronemics, and touch/haptics. Interpreting body language cues such as open vs. closed posture and gestures can provide insights into a person's emotional and mental state.