The upper right is a switch that once the metal contacts the receiving end will complete the circuit. The light is what is powered when the circuit is completed by the switch. The battery which has a positive and a negative, has a lead running from positive to the switch, from the switch to the light, from the light to the negative terminal on the battery to run a complete circuit. The wire is what carries the current. Put it this way, start at the battery and run counter clockwise from there. 1, battery 2, switch 3, light 4, wire. Just a question, is this for 8th grade science learning about energy and electricity?