Computer - Ports


What is a Port?

  • A computer port is a physical docking point using which an external device can be connected to the computer.

  • A computer port can also be programmatic docking point through which information flows from a program to computer or over the internet.


  • External devices are connected to a computer using cables and ports.

  • Ports are slots on the motherboard into which a cable of external device is plugged in.

  • Examples of external devices attached via ports are mouse, keyboard, monitor, microphone , speakers, etc.


Following are few important types of ports:

Serial Port

  • Used for external modems and older computer mouse.

  • Two versions: 9 pin, 25 pin model.

  • Data travels at 115 kilobits per second.

Parallel Port

  • Used for scanners and printers

  • Also called printer port.

  • 25 pin model.

  • Also known as IEEE 1284-compliant Centronics port.

PS/2 Port

  • Used for old computer keyboard and mouse

  • Also called mouse port.

  • Most of the old computers provide two PS/2 ports, each for mouse and keyboard.

  • Also known as IEEE 1284-compliant Centronics port.

Universal Serial Bus (or USB) Port

  • Can connect all kinds of external USB devices such as external hard disk, printer, scanner, mouse, keyboard, etc.

  • Introduced in 1997.

  • Most of the computers provide two USB ports as minimum.

  • Data travels at 12 megabits per second.

  • USB compliant devices can get power from a USB port.

VGA Port

  • Connects monitor to a computer's video card.

  • Has 15 holes.

  • Similar to serial port connector but serial port connector has pins, it has holes.

Power Connector

  • Three-pronged plug

  • Connects to the computer's power cable that plugs into a power bar or wall socket.

Firewire Port

  • Transfer large amounts of data at very fast speed.

  • Connects camcorders and video equipments to the computer

  • Data travels at 400 to 800 megabits per second.

  • Invented by Apple

  • Three variants: 4-Pin FireWire 400 connector, 6-Pin FireWire 400 connector and 9-Pin FireWire 800 connector


  • Connects a PC's modem to the telephone network.

Ethernet Port

  • Connects to a network and high speed Internet.

  • Connects network cable to a computer.

  • This port resides on an Ethernet Card.

  • Data travels at 10 megabits to 1000 megabits per second depending upon the network bandwidth.

Game Port

  • Connect a PC to a joystick.

  • Now replaced by USB.

Digital Video Interface, DVI port

  • Connects a Flat panel LCD monitor to the computer's high-end video graphic cards.

  • Very popular among video card manufacturers.


  • Connect microphone, speakers to sound card of the computer