"USB" stands for universal serial bus. USB is a type of connector which allows the user to attach peripheral devices to his computer. You can use USB to connect your printer, scanner, digital camera, mouse, external hard drive and many other devices. USB greatly simplifies the installation of hardware on a computer, and allows devices to be attached and detached while the computer is operating.
Developed by Intel, USB allows up to 127 devices to be attached to your computer. Hi-speed USB 2.0 operates at speeds up to 480 megabits per second (Mbps). USB 1.0, which was released in 1995, only supported speeds up to 12 Mbps. Wireless USB uses Ultra-Wideband (UWB) radio to connect devices to a computer. USB supports plug and play, which triggers your computer to automatically install hardware when it's plugged in.
Attaching your device to your computer by USB will start the New Hardware Wizard in Windows. Your computer will automatically install the necessary hardware if it's readily available. If a CD came with your hardware, or if you downloaded the software from the Internet, browse to the drive and folder where the software is located. Before you disconnect your device, always click on the "Safely Remove Hardware" icon in the Systray.
USB greatly simplifies hardware installation. Anyone who has worked with Windows 3.1 or 95 probably remembers IRQ conflicts--dip switches and jumpers that had to be manually set, and other installation nightmares. If you use USB with an advanced operating system like Windows 98 SE, XP or Vista, you will never again have to open the case on your computer to solve a hardware installation problem.
There are two types of USB connections. They are labelled "A" and "B." The "A" connector is the flat connector that plugs into your computer. The "B" connector is the rectangular keyed connector that you plug into your device. The "B" connector comes in different sizes depending on which device you're attaching to the computer. Small devices such as digital cameras come with USB cables with a very small "B" plug, and larger devices, such as printers, come with the bulkier "B" plug.
There are so many devices now that use USB, you may run out of connections. If this happens, you can get a USB hub to extend the number of USB ports on your computer. Simply plug the hub into the USB port on your computer, and plug your devices into the hub. USB is not supported under some older operating systems. For example, the retail version of Windows 95 did not support USB, but some later OEM releases did. There is no USB support at all in Windows 3.1. The best way to get USB to work on your older computer is to upgrade to Windows 98 SE or Windows XP.