Hard drives are the main storage area of most computers. If were to open up the metal case of a traditional hard drive, what you will see are disks on top of one another. The hard drive works much like an old record player. It has an arm that reads the data from the disks. Just like records, when the disks get damaged, they can become unreadable. Signs of hard drive failure include:
1. An ugly mechanical sound emanating from your computer
2. An error saying the computer cannot find the hard drive or
3. The computer, upon startup, will immediately go into startup repair and the operating system never loads.
If a hard drive has truly failed, the only way to get the data off is by taking it a professional with access to very specialized equipment.