If hardware gets destroyed by fire, theft (500000 notebooks are stolen each year!, use cable locks), (electro)magnetic fields, or simply if the hard disk crashes, then data is usually lost as well.
You may involuntarily erase some documents, But then you can retrieve them from the recycle bin. Overwriting files is worse.
is usually only necessary for your data and your settings, not for your programs. (This is one of the reasons why you should keep your data and your programs apart on the hard disk). You should backup your data regularly and systematically!
| Method | Advantage | Disadvantage |
| full | everything together, easy to find | expensive (time and storage) |
| incremential: Save only the recently changed files | less time and storage needed | more time necessary to restore a file |
| differential: Save only files that have been changed since last full backup. | between | between |
In Windows, use Start-Programs-Accessories-System Tools-Backup.
In companies, you need recovery plans, and you should store them at different locations outside of the IT area. According to a survey of the PR firm Stautner&Stautner, the most common reasons (in Austrian companies) for IT problems were
Erich Prisner, August 2003