This is a bedroom light circuit diagram. This circuit gives you enough time to reach the bed and lie down, and then the bedroom lights will automatically turn off. You can find many applications for this circuit. When the circuit is inactive, almost no power is consumed. What is a circuit diagram? A circuit diagram is a graphical representation of an electrical circuit that employs either simple representations of parts or industry standard symbols. The use of symbols is determined by the audience that is examining the graphic. These two forms of circuit diagrams are known as pictorial and schematic style. A schematic style circuit diagram is used to provide an electrician with a visual depiction of an electrical circuit. The visual circuit diagram would be utilized for a more general, non-technical audience.