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.
Here one ground fault circuit interrupter protects multiple duplex receptacles coming after it, known as multiple-location protection. Two-wire cable runs from the gfci to all the following receptacles. The line terminals on the gfci are connected to the circuit source and the load terminals are connected with a pigtail splice to each of the following receptacles. This keeps each duplex connected directly to the gfci.
Here two receptacles in one box are wired using the device terminals. With this arrangement, if receptacle #1 fails, receptacle #2 may also fail if failure is due to physical damage. However, if the copper tab conductors between the terminals remain intact, even if #1 stops functioning, receptacle #2 will probably still work.
This gfci wiring provides protection to a duplex receptacle. By connecting the load terminals on the last gfci, the receptacle is protected and can be used just as if it were one of the gfci receptacles. One ground fault circuit interrupter at the beginning of the circuit can be used in the same way to protect multiple, subsequent receptacles as illustrated in the diagram below.