Have you taken a good look at the back of your computer lately? If you haven't, you probably don't know about the gold mine of ports that let you connect more devices.
Macintosh and IBM-compatible computers come with some standard ports you probably know about already, and some other ports that may be less familiar.
Some of the standard ports include the following:
A mouse port. The mouse port is usually circular and located  next to the keyboard port on recent models of Macintosh and IBM-compatible computers. On the Macintosh, this port is often called the "ADB" port (shown), which stands for Apple Desktop Bus. ADB ports allow you to connect more than one device through that port, so you can plug your mouse into an ADB port on the keyboard, which is then plugged into an ADB port on the back of the computer. This scheme is now used on some IBM-compatibles, but they don't use the ADB name.
A keyboard port. Like the mouse port, most keyboard ports are also circular. Older IBM-compatibles have larger, five-pin ports, while newer machines have smaller ports with holes for six pins (ps/2). They are commonly labeled with "KYBD" or "Keyboard" on IBM-compatible computers, or with three squiggly lines on Macintosh computers.
Be careful when plugging in a keyboard or a mouse on a PC computer: The keyboard and mouse ports are similar, and connecting the wrong device to the wrong port can cause problems.
On older Macintosh computers that have both keyboard and mouse ports, both are ADB-compatible, so you can interchange different devices with different ports.
Printer/FAX ports. The majority of PC computer users have parallel printers that plug into the parallel port of the computer. Macintosh users are more likely to use printers that connect to a serial port.
Spotting these ports is easy: On IBM-compatible computers, the parallel port is a long, black strip with two rows of holes (25 in all). Confirm its identity by the label or in the user's manual to make sure you don't confuse it with a SCSI or some other port. The parallel port can send data to a single-user parallel printer/fax machine, and it is controlled by a device driver. Parallel ports can also be used to connect other devices to the computer, including Zip drives, tape backups and scanners. Typically, you'll plug the drive or scanner into the parallel port and then plug the printer into a port on the drive or scanner.
On Macintosh computers, the printer port is easy to find because it's marked with an icon resembling a printer. This port can send data to a single-user printer, or can double as a low-speed networking port, allowing you to communicate with other computers or printers over a network.
It's important to note that MOST printers/fax machines/scanners sold today are connected using a USB port. However, pc's still accomodate the use of parallel connectivity for other devices that still use it.
. On both IBM-compatible and Macintosh computers, serial ports connect external modems to your computer.
You can spot a serial port on a PC by looking for a plug with nine pins lined up in two rows. (When pins are sticking out of a plug or port, it's called a "male" connector; when holes are present on a plug or port, it's called a "female" connector.) Oftentimes, a PC's serial port is located very close to the keyboard and mouse ports. In some cases, an IBM-compatible computer will come with two serial ports. Older PCs may have larger, flat serial ports with 25 pins.
The Macintosh modem port (shown) is a female connector branded with an icon resembling the handset of a phone. Actually, Macintoshes only have serial ports. The printer port (see description above) is identical to the modem port; they are only named as such to make selection easier and more intuitive than the labels "port 1" and "port 2."
Serial ports are utility players on IBM-compatibles as well: They can connect not only external modems but also printers, mice and scanners. They can also connect two computers together to allow file copying and sharing. Because they're so flexible, serial ports can also be used to connect other devices, such as testing or monitoring equipment.
Again, USB connectivity is becoming the standard for hooking most all external peripheral devices today's pc's.
. These ports come in a variety of sizes. Most computers now come with built-in monitor ports. However, if you're using an older computer, you might find that your monitor is connected to a video card via an expansion slot plugged into the computer's motherboard.
In terms of size, monitor ports fall somewhere between serial ports and parallel ports. You'll typically see a 15-pin configuration on a monitor port, but they also come in nine-pin female and 25-pin male (the same configuration as a parallel port) arrangements.
On Macintosh computers, the monitor port is a 25-pin female designated by an icon resembling a computer screen.
You'll find these flat black ports on many computers. They're designed for a today's generation of printers, scanners, monitors, digital camera's, cell phones, portable storage drives and modems. Essentially, any external peripheral device today can be connected via a USB port. USB is generally considered to be 'plug-and-play' capable, which means that your computer does not have to be turned off and restarted in order for the pc to recognize the new device being plugged in. This is especially beneficial in the case of utilizing portable storage devices like hard drives and thumb drives.
They're much faster than standard serial or parallel ports, and can be 'daisy-chained' from a USB hub to allow for additional connections beyond the ports built into the system. By design, you'll be able to connect up to 127 devices to a single USB port.
Besides these common (and essential) ports, personal desktop computers often come with a number of other connectors that offer even more ways to link up external devices. These ports include the following:
SCSI, which stands for Small Computer System Interface, offers expandability and versatility over and above all other types of ports. A SCSI port (pronounced "scuzzy" port) can connec t up to seven devices on a daisy chain (an internal hard disk drive may count as one). These extra devices can include scanners, hard disk drives and CD-ROM drives, just to name a few.
SCSI ports are common features on Macintosh computers. Only the newest models of high-end PC computers offer built-in SCSI ports. Other PC users must add an expansion card to augment their computer with a SCSI port.
Many  models of computer come with built-in female connectors that allow you to connect external speakers, as well as jacks that allow you to connect microphones for recording on or controlling your computer.
Your Computer will either have the microphone and speaker port jacks located directly on the motherboard, or on a sound card, an extra element that fits into an expansion slot on the inside of the computer.
These flat, 15-pin ports are used to control the joystick (or other gaming device) on a computer. On some PCs with sound cards, the port also can be used as a connector for musical keyboards, drum pads and other devices that adhere to the Musical Instrument Digital Interface standard (MIDI).
Caution: Computer manufacturers recommend that you not change any non-USB connection while the computer and/or external device are turned on, as costly damage may occur. Some connectors, such as SCSI ports, are particularly susceptible. You might be able to plug and unplug a powered device hundreds of times without a problem, but there is always a risk. |