Once your system is in use, your next consideration should be to back up the file systems, directories, and files. Files and directories represent a significant investment of time and effort. At the same time, all computer files are potentially easy to change or erase, either intentionally or by accident. If you take a careful and methodical approach to backing up your file systems, you should always be able to restore recent versions of files or file systems with little difficulty.
Note: When a hard disk crashes, the information contained on that disk is destroyed. The only way to recover the destroyed data is to retrieve the information from your backup copy.
There are several different methods of backing up. The most frequently used method is a regular backup, which is a copy of a file system, directory, or file that is kept for file transfer or in case the original data is unintentionally changed or destroyed. Another form of backing up is the archive backup; this method is used for a copy of one or more files, or an entire database that is saved for future reference, historical purposes, or for recovery if the original data is damaged or lost. Usually an archive is used when that specific data is removed from the system.
This section discusses: