Network card

The network card allows your computer to communicate over a network. With the network card you can set up a home network with a few computers and connect them by via Ethernet cords or wirelessly. Network cards used to be expansion cards that plugged into the motherboard; however, most newer computers have a network interface built into the motherboard.

Power Supply Unit Power Supply Unit
The power supply unit in a computer converts the power from the wall outlet to the type of power needed by the computer. It sends power through the cables to the motherboard and other components.