It is vital that you make backup copies of the files on your computer on a regular basis so you don't lose valuable data if your computer encounters problems. The term back up (or backup , when referring to the noun or adjective) refers to the process of using a special software program designed to read your data quickly, compress it into a small, efficient space, then store it on an external medium, such as a set of disks or a tape cartridge.
Windows XP Professional includes a program called Backup. Using Backup has several advantages over simply copying files to a removable disk. Your files are compressed as they are copied so that you can fit more onto a removable disk, and it splits a large file across two or more disks (saving disk space), something you cannot do with the Copy command. Also, in an emergency, Backup offers several data-recovery aids to help you locate and restore important files quickly.
If your computer system crashes and Windows XP cannot start, you can't use Backup to restore the files. To avoid the event of a major system failure and prepare for possible problems in the future, you can use the Automated System Recovery Preparation Wizard to help you create an Automated System Recovery (ASR) disk and backup of your system files. The ASR disk and the Windows XP installation CD allow you to start Windows XP and retrieve a backup of your system and personal files to restore your system.