To wire an exhaust fan to a wall switch, use this diagram. These fans usually come with a small electrical connection box welded to the side of the housing. There will be a cover on the connection box that fastens with a small screw. Open it, pop the plug out of one of the wire holes and thread a wire clamp into it.
The black cable wire is connected to the top terminal on the switch and spliced to the black and blue wires at the fan at the other end. The neutral source and ground are spliced through to the white and ground connections at the fan.
In this diagram, a light switch and receptacle are wired in the same box. Both devices are spliced to the same hot source and the neutral to the neutral on the receptacle, and through to the light fixture located in a separate box.
Here 3-wire cable is run from a double-pole circuit breaker and split to supply 120 volts to two sets of receptacles. The neutral wire from the circuit is shared by both. This wiring is commonly used in a 20amp kitchen circuit where two appliance feeds are needed, such as for a refrigerator and a microwave in the same location.