The back panel of your PC’s tower that you plug peripherals into is called the I/O panel (see the following figure). The items you find on your PC’s I/O panel may be labeled with text, or they may be denoted with certain symbols.
The following list describes the items shown in the figure:
Keyboard: The keyboard plugs into this little hole.
Mouse: It’s generally the same size and shape as the keyboard connector, although this hole has a mouse icon nearby to let you know that the mouse plugs in there.
USB: Plug snazzy devices into these Certs-size Universal Serial Bus (USB) slots.
COM/Serial: PCs have at least one of these connectors.
Video/VGA: Your PC’s monitor can plug into this hole. The video connector is about the same size as the COM/serial connector, but it has 15 holes rather than 9.
SPDIF In, SPDIF Out: These connectors are used for digital audio. Special fiber optic cable is required: Audio coming into the computer plugs into the In hole; the sound the computer generates goes out the Out hole.
Headphones/speakers: Into this hole you plug in your PC’s external speakers or headphones, or it’s where you hook up the PC to a sound system.
Line In: This jack is where you plug a traditional audio-producing device (stereo, phonograph, VCR, and so on) into the PC for capturing sound.
Surround left/right: Also for surround sound, this is the jack into which you plug the rear left and right speakers.
Center/subwoofer: For a surround sound audio system, you plug the center speaker or subwoofer, or both, into this jack.
Microphone: The computer’s microphone plugs into this jack.
Modem: This is where you connect your PC’s dialup modem to the phone jack in the wall. If two phone or modem holes are on the I/O panel, the second one is for a telephone extension.
Network: This is where you plug in a local area network (LAN) connector or where you attach a broadband modem to the PC.
Printer: Older printers can plug into this connector.
Mini 1394: This special version of the IEEE 1394 connector is designed specifically for digital video and for connecting digital cameras.
IEEE 1394 (FireWire): This is another type of versatile connector, similar to USB.
