Peripheral Devices

General information

A peripheral device is anything that you connect to your computer using a USB or firewire port. For example a mouse, a USB memory key and an external hard drive are all examples of peripheral devices.

A peripheral device such as a mouse, which is not involved in transferring files between computers, can be detached by removing the cable from the port. However, for devices that can be used to transfer files, such as USB key or an external hard drive, it is very important to eject the device before detaching it from the computer. The reason for this is that in some cases, you do not know whether the device and your computer are still communicating with one another (files/folders are still being transferred etc). If this is the case and you remove the device too soon, you risk loosing or damaging the data that was being transferred. To make sure that this doesn't happen, you need to ask the computer to eject the device. The computer will only eject the device once it has finished communicating with it.

When a peripheral device that is used to transfer data is detected by your computer, a little symbol like this appears in the Task bar near the clock.

Note: by ejecting, we are not talking about a physical ejection - you still have to physically remove the device yourself. The word eject is used here as a metaphor to mean that the computer signals that it's done with the device and doesn't need it anymore.


To eject a peripheral device

There are three ways to eject a peripheral device safely. The first two are to:

  • open the My Computer window, right-click on the peripheral device (usually labeled Removable Disk) and select Eject from the contextual menu
  • open the My Computer window, select the peripheral device (usually labeled Removable Disk) and then select Eject this Disk from the Common Tasks pane of the window

In these two cases, if a file or folder on the peripheral device is being used, or a file or folder is being copied to it, you will get a warning messaging that the device is in use and that you might loose data if you continue with the ejection. You can then stop the ejection, or choose to continue.

The third option, and usually the best and easiest way to do it, is to:

  • click on the icon in the Task bar and then on the Safely Remove Hardware box that appears.

You will get a box similar to the one below on the left:

If the device that you want to eject is not highlighted (like above) select it using the mouse. Once the device is selected, press the Stop button. You will get a confirmation window (above right) asking you verify that you really want to stop the device. Again, select the device that you want to stop, and click OK. If the device is not being used, a pop-up will appear near the icon which will say that it is safe to remove the device, and the icon will disappear from the Task bar. Once this happens, you can remove the device.