From The Art and Popular Culture Encyclopedia
Interpersonal communication is defined by communication scholars in numerous ways, though most involve participants who are interdependent on one another, have a shared history. Communication channels are the medium chosen to convey the message from sender to receiver. Communication channels can be categorized into two main categories: Direct and Indirect channels of communication.
Direct channels are those that are obvious and can be easily recognized by the receiver. They are also under direct control of the sender. In this category are the verbal and non-verbal channels of communication. Verbal communication channels are those that use words in some manner, such as written communication or spoken communication. Non-verbal communication channels are those that do not require words, such as certain overt facial expressions, controllable body movements (such as that made by a traffic police to control traffic at an intersection), color (red for danger, green means go etc), sound (sirens, alarms etc.).
Indirect channels are those channels that are usually recognized subliminally or subconsciously by the receiver, and not under direct control of the sender. This includes kinesics or body language, that reflects the inner emotions and motivations rather than the actual delivered message. It also includes such vague terms as "gut feeling", "hunches" or "premonitions".
Channels means mode of communicating the messages.
Participants is the communicators who are both senders and receivers.
Context refers to the interrelated conditions of communication. It consists of everything that is not in the message, but on which the message relies in order to have its intended meaning. Ultimately, context includes the entire world, but usually refers to such salient factors as the following:
Situational milieu, for example: classroom, battlefield, supermarket
Cultural and linguistic background of each participant, how similar? how different?
Emotional state and developmental stage of each participant
Social role enacted by each participant, for example: boss, employee, teacher, student, parent, child, spouse, friend, enemy, partner, competitor