In this wiring, the source is at the switch and 3-wire cable runs from there to the fan/light. The switch controls the light and the source is spliced through to the fan. With this arrangement, the fan is controlled by a pull-chain on the motor housing and the light is controlled with the switch. The neutral and ground wires are also spliced through to the fan/light.
In this wiring, a switch and receptacle are in the same box and the switch controls the power to the outlet. The hot wire connects to the bottom terminal on the switch and the top output goes to the receptacle hot terminal. The neutral wire from the source connects directly to the receptacle neutral.
In this arrangement with 2 switches in one box, the bottom terminals are connected to pigtails spliced to the source. The top switch terminals connect to the black wires running to the light fixtures. The source neutral and ground wires are spliced to run to each light box.
Here GFCI’s are wired to a double-pole circuit breaker with the source split to provide 120 volts to two sets of receptacles. The neutral from the source is shared by both sets. Single-location protection is provided by each receptacle.