Intrapersonal communication is communication with oneself. Obviously, only one person is involved and there are limitless opportunities for the individual to communicate.

Interpersonal communication is communication between two people. Each person can potentially contribute to the conversation about 50 % of the time, with rapid exchange of information.

Group communication occurs with three to approximately ten people. With more people involved, there is less opportunity for each individual to contribute to the discussion. Also, there is greater need for one or more members of the group to control or direct the conversation.

Public communication involves ten or more people communicating in person. Because of the large number present, only one person at a time can address the group, so individuals generally spend most or all of the time listening, with little opportunity to speak to the others.

Mass communication requires electronic technology in which a few persons may communicate to many people at one time through public address systems, radio, television, or computers. The number of people involved can reach into the millions, but individuals have little or no opportunity to contribute to the messages being sent over the electronic media. This communication is usually one-sided, so feedback from the receivers is delayed, if it can be sent at all.