The document discusses principles of communication including definitions, concepts, theories, and elements. It defines communication as the sharing of ideas and feelings between two or more people through various channels and symbols. Two key theories of communication mentioned are cognitive dissonance theory, which discusses how people seek to avoid conflicting beliefs, and communication accommodation theory, which examines how people adjust their communication styles when interacting with others. The document also outlines the basic components and cycle of the communication process, including the sender, message, medium, receiver, and potential issues that can occur at each stage.