 A typical USB connector. See more USB pictures. |
In this article, we will look at USB ports from both a user and a technical standpoint. You will learn why the USB system is so flexible and how it is able to support so many devices so easily -- it's truly an amazing system!
Anyone who has been around computers for more than two or three years knows the problem that the Universal Serial Bus is trying to solve -- in the past, connecting devices to computers has been a real headache!
- Printers connected to parallel printer ports, and most computers only came with one. Things like Zip drives, which need a high-speed connection into the computer, would use the parallel port as well, often with limited success and not much speed.
- Modems used the serial port, but so did some printers and a variety of odd things like Palm Pilots and digital cameras. Most computers have at most two serial ports, and they are very slow in most cases.
- Devices that needed faster connections came with their own cards, which had to fit in a card slot inside the computer's case. Unfortunately, the number of card slots is limited and you needed a Ph.D. to install the software for some of the cards.
The goal of USB is to end all of these headaches. The Universal Serial Bus gives you a single, standardized, easy-to-use way to connect up to 127 devices to a computer.
Just about every peripheral made now comes in a USB version. A sample list of USB devices that you can buy today includes:
- Printers
- Scanners
- Mice
- Joysticks
- Flight yokes
- Digital cameras
- Webcams
- Scientific data acquisition devices
- Modems
- Speakers
- Telephones
- Video phones
- Storage devices such as Zip drives
- Network connections
In the next section, we'll look at the USB cables and connectors that allow your computer to communicate with these devices.
