Nonverbal communication is the transmission of messages or signals through a nonverbal platform such as eye contact (oculesics), body language (kinesics), social distance (proxemics), touch (haptics), voice (prosody and paralanguage), physical environments/appearance, and use of objects. When communicating, nonverbal channels are utilized as means to convey different messages or signals, whereas others interpret these messages. The study of nonverbal communication started in 1872 with the publication of The Expression of the Emotions in Man and Animals by Charles Darwin. Darwin began to study nonverbal communication as he noticed the interactions between animals such as lions, tigers, dogs etc. and realized they also communicated by gestures and expressions. For the first time, nonverbal communication was studied and its relevance noted. Today, scholars argue that nonverbal communication can convey more meaning than verbal communication.

In the same way that speech incorporates nonverbal components, collectively referred to as paralanguage and encompassing voice quality, rate, pitch, loudness, and speaking style, nonverbal communication also encompasses facets of one's voice. Elements such as tone, inflection, emphasis, and other vocal characteristics contribute significantly to nonverbal communication, adding layers of meaning and nuance to the conveyed message. However, much of the study of nonverbal communication has focused on interaction between individuals, where it can be classified into three principal areas: environmental conditions where communication takes place, physical characteristics of the communicators, and behaviors of communicators during interaction.

Nonverbal communication involves the conscious and unconscious processes of encoding and decoding. Encoding is defined as our ability to express emotions in a way that can be accurately interpreted by the receiver(s). Decoding is called "nonverbal sensitivity", defined as the ability to take this encoded emotion and interpret its meanings accurately to what the sender intended. Encoding is the act of generating information such as facial expressions, gestures, and postures. Encoding information utilizes signals which we may think to be universal. Decoding is the interpretation of information from received sensations given by the encoder. Culture plays an important role in nonverbal communication, and it is one aspect that helps to influence how we interact with each other. In many Indigenous American communities, nonverbal cues and silence hold immense importance in deciphering the meaning of messages. In such cultures, the context, relationship dynamics, and subtle nonverbal cues play a pivotal role in communication and interpretation, impacting how learning activities are organized and understood.

According to some authors, nonverbal communication represents two-thirds of all communications^[clarify]. Nonverbal communication can portray a message both vocally and with the correct body signals or gestures. Body signals comprise physical features, conscious and unconscious gestures and signals, and the mediation of personal space. The wrong message can also be established if the body language conveyed does not match a verbal message. Paying attention to both verbal and nonverbal communication may leave the listener with a feeling of being lost, due to not being able to breakdown both at the same time. However, ignoring nonverbal communication altogether would cause the listener to miss up to 60% of their communication, according to experts.

Nonverbal communication strengthens a first impression in common situations like attracting a partner or in a business interview: impressions are on average formed within the first four seconds of contact. First encounters or interactions with another person strongly affect a person's perception. When the other person or group is absorbing the message, they are focused on the entire environment around them, meaning the other person uses all five senses in the interaction: 83% sight, 11% hearing, 3% smell, 2% touch and 1% taste.

Many indigenous cultures use nonverbal communication in the integration of children at a young age into their cultural practices. Children in these communities learn through observing and pitching in through which nonverbal communication is a key aspect of observation.

According to Judee K. Burgoon et al., further reasons for the importance of non-verbal communication are:

Nonverbal communication encompasses a diverse range of signals that go beyond spoken language, such as gestures, facial expressions, body language, and vocal nuances like tone and rhythm. These cues carry subtle meanings critical to effective communication. For example, facial expressions are a powerful medium for conveying emotions, sometimes even through subtle microexpressions. These microexpressions are fleeting, involuntary facial movements that briefly reveal genuine feeling. They often occur in a fraction of a second, offering a brief insight into a person's genuine emotions, some of which may not be intentionally expressed and may diverge from their consciously stated feelings. While some cues might be universally understood, others hold culture-specific significance, necessitating careful interpretation to prevent misunderstandings. Understanding the tone, pitch, cultural connotations of touch, and environmental influences enriches nonverbal communication, shaping our interactions. Recognizing that cultural norms influence the appropriateness of tone and pitch is crucial, as outlined by display rules. This underscores the significance of being culturally sensitive when interpreting nonverbal cues. In the context of intercultural communication, a deeper understanding of context culture becomes essential. Context culture significantly shapes how individuals communicate emotions and convey meaning through nonverbal signals. Being aware of these cultural nuances is fundamental for facilitating successful cross-cultural interactions and ensuring the accurate interpretation of nonverbal expressions.