The power port is a port on a computer or other electronic device that allows it to get power from a wall outlet and charge the device's battery if capable. Devices like desktop computers, which don't have batteries, cannot turn on without a power cord connected to the power port. Devices like laptops, which typically have a battery, can work with or without anything connected to the power port if the battery has a charge.
Connecting a cord to the power port
Below are all the different ways a cord can be connected to a power port on a computer or other hardware device.
Desktop computer power port
For most desktop computers, the power port is part of the power supply, which connects to the motherboard inside the computer. This port is on the back of the computer at the top or bottom of the chassis. The picture is of an Antec power supply removed from a computer and a visual example of the back of the power supply. In this example, the power port is found on the top right corner of the back of the power supply.
For an all-in-one computer, because it's thinner than a traditional desktop chassis, the power port is more like that of a laptop. These power ports are located on the back of the computer, either in the bottom left, right, or center.
Laptop power port
Most laptops use an AC adapter for connecting the laptop from the power outlet to the power port. The power port location varies by laptop manufacturer but is often found on the back or back corner of the laptop. In the picture of an AC adapter, the power brick used to convert the power signal, and the cable that connects the power brick to the power port is shown. An additional power cord would be connected from the brick to a wall outlet, shown in this example.
Smartphone and tablet power port
Over the evolution of smartphones and tablets, many different power ports used. Thankfully, most companies are moving to the USB Type-C connector. This power port connector can be found on all modern Android phones and tablets, and Apple iPads. Unfortunately, all modern Apple iPhones are still using the Lightning connector.
A power adapter is used to plug these connectors into the wall outlet. Otherwise, a computer with a USB or Thunderbolt port can be used as a power port to charge and power these devices.
Printer power port
The printer power port is found on the back or back corner of the printer.
Monitor, TV, and other display devices
For very thin displays, the power cord may use an AC adapter to help convert the power signal.