Non-verbal communication conveys important messages through facial expressions, gestures, eye contact, posture, proximity and other cues. Despite being continuous and sometimes involuntary, non-verbal signals can be ambiguous and open to misinterpretation. They predominantly relate to relationships and reveal emotions, attitudes and inner states that are not easily expressed verbally. Different aspects of non-verbal communication include kinesics (body movement), proxemics (use of space), chronemics (aspects of time), and paralanguage (voice qualities and vocal cues). Together, non-verbal signals modify, reinforce and sometimes contradict what is said.