Minimizing Hard Disk Drive Failure and Data Loss/Additional Measures
A particularly malicious or buggy virus can cause data loss, typically without any resultant physical damage to the underlying drive. Additionally, in theory, a virus can stress a particular portion of a drive to the point that the drive has an error. Antivirus software and other measures exist to combat these and other threats posed by viruses.
Revision control is an essential technique for avoiding data loss. In particular, it guards against data loss caused by a user.
It is useful only for files that may be modified, such as documents, spreadsheets, logos, and source code. As such, revision control contrasts with parchives, which applies to files that do not get modified.
Having a backup does not obviate revision control. This is because revision control by and large ensures that a file can be reverted to any of its older versions, whereas a backup does not offer this guarantee.