A hard drive that is outside of the computer case in its own enclosure. Most support the IDE interface and are slightly bigger than a hard drive itself. When purchasing an external hard drive you can buy a full external hard drive system that consists of both the hard drive and the enclosure, or you can purchase just the enclosure to hold your own hard drive. External hard drives may contain a fan for cooling and are popular because they are portable devices and can be stored securely under lock and key since they are not inside the computer case. An external hard drive is connected to the computer system with a single high-speed interface cable, usually with plug-and-play interfaces such as USB or FireWire.A hard drive is a computer component that holds data. Every computer needs at least one hard drive to store its operating system, programs and user information. This drive is usually internal, however, as computer systems have evolved and different needs, threats, and circumstances have arisen, the additional external hard drive has become extremely popular.
Internet access regularly exposes computers to potential security threats like Trojan horses, viruses and spyware. It has become increasingly difficult to guard against these threats, even when employing firewalls and antivirus programs. Aside from online threats, multiple family members often use the same system, putting sensitive documents at higher risk of inadvertent corruption or loss. Additionally, the space required for multimedia storage has soared with MP3s, streaming video, DVD burning, and photo files taking up large amounts of space on the hard drive. All of these unrelated concerns can be addressed with one simple answer: an external hard drive.
An external hard drive sits outside the main computer tower in its own enclosure. The enclosure is slightly larger than the hard drive itself, and sometimes contains a cooling fan. This portable encasement allows the user to store information on a hard drive that is not inside the computer, but rests on a tabletop or surface nearby the computer. The external hard drive is connected to the computer via a high-speed interface cable. The interface cable allows the external hard drive to communicate with the computer so that data may be passed back and forth. The most common types of interfaces are USB and Firewire.
A portable or external hard drive is quite a useful piece of equipment. It allows the user to back up or store important information separate from the main internal hard drive, which could become compromised by online or offline activities. Sensitive documents, large music files, DVD images, movies, disk images, and even a backup of the contents of your main internal hard drive, can all be kept securely and safely on an external hard drive. When you are online, you can even leave the external drive turned off.
Another advantage of an external hard drive is that it is portable and operates on a plug-and-play basis. Any computer with USB or Firewire capability will recognize the external hard drive as a storage device, and assign it a letter to designate it. The drive can then be accessed like a normal internal hard drive. It's a snap to transfer huge files back and forth from work to home, to a friend's house, or between your desktop and laptop. Just plug in the interface cable to quickly reconstruct a working environment, making your favorite programs virtually portable.
If you have multiple family members using your computer system, consider an external hard drive to keep financial information and other sensitive documents secure. When you are ready to use the computer, you can plug in the external drive and have all your data and programs available. When finished, simply unplug the drive and take it with you to lock in a drawer or other secure location.
There are inexhaustible reasons to use an external hard drive. You can even buy several hard drives and swap them in and out of the same enclosure, using one for multimedia storage, one for imaging, one for backup, one for work, and so on.
reff : wepopedia.com, wisegeek.com
