Computer Basics

Expansion cards

Most computers have expansion slots on the motherboard that allow you to add various types of expansion cards. These are sometimes called PCI (peripheral component interconnect) cards. You may never have to add any PCI cards, as most motherboards have built-in video, sound, network, and other capabilities. However, if you want to boost the performance of your computer or update the capabilities of an older computer, you can always add one or more cards. Below are some of the most common types of expansion cards:

Video card

A video card

The video card is responsible for what you see on the monitor. Most computers have a GPU (graphics processing unit) built into the motherboard, instead of having a separate video card. If you like playing graphics-intensive games on the computer, you can add a faster video card to one of the expansion slots to get better performance.

Sound card

The sound card, also called an audio card, is responsible for what you hear in the speakers or headphones. Most motherboards have integrated sound, but you can upgrade to a dedicated sound card for higher-quality sound.

Network card

The network card allows your computer to communicate over a network and access the Internet. It can either connect with an Ethernet cable or through a wireless connection (often called Wi-Fi). Many motherboards have built-in network connections, and a network card can also be added to an expansion slot.

Bluetooth card

A Bluetooth dongle

Bluetooth is a technology for wireless communication over short distances. It's often used in computers to communicate with wireless keyboards, mice, and printers. It's often built into the motherboard or included in a wireless network card. For computers that don't have Bluetooth, a USB adapter (called a dongle) can be purchased.