Communication is key to any kind of interaction with people. It helps us accomplish common goals, empathize with each other, or persuade of another opinion. Communication also informs people around us who we are and what we think.
Communication is an awesome tool, but it can do much damage if not used properly. This holds true in all types of situations.
As (hopefully) everyone knows, communication is a two-way street for the parties involved. If you are attempting to communicate with another person, you convey information, and they convey information. The key is for each of you to accept the conveyed information. I'm not talking about just "hearing" or "seeing", but interpreting and understanding. If one of you interprets the information incorrectly, it could result in something as small as a simple misunderstanding or as large as an personal insult (that does lasting emotional damage).