This document discusses corporate communication and the different types of communication channels within a business organization. It describes formal communication as flowing along the official chain of command in writing, along established lines of authority. Informal communication occurs through unofficial social relationships. Vertical communication moves up and down the hierarchy, while horizontal/lateral communication occurs between peers. Diagonal communication crosses standard lines. The grapevine is an informal network that spreads information quickly but risks distortions. Barriers to effective communication include semantic issues, organizational complexity, emotional/perceptual differences, and physical/environmental challenges.