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Why USB 2.0?
Universal Serial Bus (USB) 2.0 is an external serial interface used on computers and other digital devices to transfer data using a USB cable. The designation “2.0” refers to the standard or version of the USB interface. As of fall 2006, USB 2.0 remains the current standard.
USB is a plug-and-play interface. This means that the computer does not need to be powered off in order to plug in or unplug a USB 2.0 component. For example, an iPod or other MP3 player can be connected to a computer via a USB cable running to the USB 2.0 port. The computer will register the device as another storage area and show any files it contains.
Using the USB 2.0 interface, one can transfer files to or from the MP3 player. When finished, simply unplug the USB cable from the interface. Because the computer does not need to be shut down to plug in the device, USB components are considered “hot swappable.”
Aside from MP3 players, many other external devices use USB 2.0 data ports, including digital cameras, cell phones, and newer cable boxes. Native components also make use of USB, such as mice, keyboards, external hard drive enclosures, printers, scanners, fax machines, wireless and wired networks keys, and WiFi scanners. One of the most popular and convenient USB gadgets is a memory stick.
When USB standards change from an existing version to a newer version, as they did from USB 1.1 to USB 2.0, hardware made for the newer version is in most cases backwards-compatible. For instance, if a computer has a USB 1.1 port, a device made for USB 2.0 that is marked as “backwards compatible to USB 1.1” will work on the older port. However, the device will only transfer data at 1.1 speeds using a USB 1.1 port.
Currently, computers are built with USB 2.0 ports. The USB 2.0 standard encompasses three data transfer rates:
* Low Speed: 1.5 megabits per second, used mostly for keyboards and mice.
* Full Speed: 12 megabits per second, the USB 1.1 standard rate.
* Hi Speed: 480 megabits per second, the USB 2.0 standard rate.
Since USB 2.0 supports all three data rates, a device that is marked as “USB 2.0 compliant” isn’t necessarily hi-speed. It may operate through a USB 2.0 port at one of the slower speeds. Look for clarification when shopping for hi-speed USB 2.0 devices.
USB is a plug-and-play interface. This means that the computer does not need to be powered off in order to plug in or unplug a USB 2.0 component. For example, an iPod or other MP3 player can be connected to a computer via a USB cable running to the USB 2.0 port. The computer will register the device as another storage area and show any files it contains.
Using the USB 2.0 interface, one can transfer files to or from the MP3 player. When finished, simply unplug the USB cable from the interface. Because the computer does not need to be shut down to plug in the device, USB components are considered “hot swappable.”
Aside from MP3 players, many other external devices use USB 2.0 data ports, including digital cameras, cell phones, and newer cable boxes. Native components also make use of USB, such as mice, keyboards, external hard drive enclosures, printers, scanners, fax machines, wireless and wired networks keys, and WiFi scanners. One of the most popular and convenient USB gadgets is a memory stick.
When USB standards change from an existing version to a newer version, as they did from USB 1.1 to USB 2.0, hardware made for the newer version is in most cases backwards-compatible. For instance, if a computer has a USB 1.1 port, a device made for USB 2.0 that is marked as “backwards compatible to USB 1.1” will work on the older port. However, the device will only transfer data at 1.1 speeds using a USB 1.1 port.
Currently, computers are built with USB 2.0 ports. The USB 2.0 standard encompasses three data transfer rates:
* Low Speed: 1.5 megabits per second, used mostly for keyboards and mice.
* Full Speed: 12 megabits per second, the USB 1.1 standard rate.
* Hi Speed: 480 megabits per second, the USB 2.0 standard rate.
Since USB 2.0 supports all three data rates, a device that is marked as “USB 2.0 compliant” isn’t necessarily hi-speed. It may operate through a USB 2.0 port at one of the slower speeds. Look for clarification when shopping for hi-speed USB 2.0 devices.
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