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.
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.
This diagram illustrates wiring a GFCI receptacle and light switch in the same outlet box, a common arrangement in a bathroom with limited space. The hot source is spliced to the LINE terminal on the receptacle and to the bottom terminal on the light switch. The neutral and ground wires are spliced together and run to each device in the circuit.