A backup is an exact copy of a file, stored in a separate location, to be restored when a problem occurs. There are several ways data can be lost or damaged. These problems can range from hardware failure, accidental deletion, natural disaster, or theft.
If there is any important data on your computer, it should be backed up, and for best results, it should be in multiple locations.
There two main types of backup: Data Backup and System Backup. Data consists of your files, music, movies, etc. System is your operating system and programs.
A third type of backup is a little more technical. It is called a system image, also known as a bare-metal backup. This is an EXACT COPY of the ENTIRE hard drive. One advantage to this is speed of recovery. In the case of a failed drive, the drive can simply be replaced, and the most recent image file copied onto it. Rather than restoring individual programs or files, a system image restore recreates the contents of the hard drive exactly as they were at the time the image was created. Some downsides are the amount of space required to make these backups, and the fact that they require more of a technical understanding of the software used to be implemented effectively.
If your backups are in multiple locations, you are protected in the case of natural disaster or theft, where you could potentially lose your computer and anything in the vicinity.
One strategy for backups is the 3-2-1 Rule, advocated by the American Society of Media Photographers. It consists of having a minimum of 3 copies of your data, on 2 different types of media (such as hard drives and DVD), and with 1 stored at a different location.
Please note: If you create a backup, it does not mean you can delete the original from your hard drive. If there is only one copy, then it is not a backup.
Most Operating Systems have built-in ways to backup and restore system files. There is also 3rd party software available that may be easier to use or contain more features. For best results, these programs will backup your system to a separate hard drive, although in some cases, they will allow you to use DVDs.
Windows XP has a Backup and Restore Utility, but it is not installed by default on Windows XP Home. There is a simple way to add it, but it requires your copy of the Windows XP Home installation CD.
Once you have the Backup and Restore Utility installed:
- Click Start, and the click Run.
- Type ntbackup.exe in the Open box, and then click OK.
The full Backup and Restore functionality is available in all Windows 7 versions.
- Click Start, and the type Backup and Restore in the search box
A complete walkthrough can be found on Microsoft's support site.
Mac OS XEdit
With the purchase of an external hard drive or a Time Capsule, one can use the builtin Time Machine feature to restore the system to a previous point. As mentioned on the Apple website, "Time Machine automatically backs up your entire Mac, including system files, applications, accounts, preferences, music, photos, movies, and documents."
Backing up files can be as simple as dragging them to a portable USB drive or copying them onto a CD. There is also software to make the process more automatic and give more fine-grain control.
In addition to making local copies of your data. There are several online services that allow you to store your data "in the cloud" (on the internet).
These are just a few examples. A more thorough list can be found on Wikipedia's List of Backup Software.
- Windows Backup and Restore
- Windows Home Server
- Mac OS X Time Machine
- Acronis True Image
- Norton Ghost
These are just a few examples. A more thorough list can be found on Wikipedia's Comparison of Online Backup Services.