Under what circumstances does a hard disk crash?How can we prevent it?

Broadly speaking a hard disk can fail in four ways that will lead to a potential loss of data:

• Firmware Corruption / Damage to the firmware zone
• Electronic Failure
• Mechanical Failure
• Logical Failure

Combinations of these four types of failure are also possible. Whether the data on the hard disk is recoverable or not depends on exactly what has happened to the disk and how bad the damage is. All hard disks also develop bad sectors which can lead to data loss and drive inaccessibility.