There is always a sender and a receiver in communication, or to be more precise, an intended receiver. In the drawing here, Angela is the sender and Bob is the receiver. Angela and Bob have different personal realities. They each have their own world formed by their experiences, perceptions, ideas, etc. They will perceive, experience and interpret things differently. The same event will be perceived differently by each person. For communication to occur, there must be some “shared space”. The participants must have some concept of each other's location and of a possible channel of communication existing between them. They must be in agreement over these concepts for communication to take place.