Hard disk failure, here are the reason and the sign of failure

Hard disk Failure, are mostly a computer hardware problem. Laptop hard disks fail more often than desktop Hard Disk. If you knock hard or drop your laptop even a few inches while it’s working, you may damage the Hard Disk.
Before involved in hard disk failure come across with the main reason we do upgrade our hard disk is to increase the storage space of user data.

Why hard disk failure?

Arm is moved by an actuator, and the read/write heads themselves hover an infinitesimal distance above the platters.
  
The distance is so small that a single piece of dust can get in the way.If any of the hard drive's mechanical parts fails, the whole drive will fail. The parts operate with incredible precision, so hard drives are rather fragile. Circuit boards, spindle motors, ball bearings -- any of these parts are susceptible to failure.

The worst type of failure is known as a head crash. In this case, the read/write head drops down directly onto the platter and scrapes away the magnetic material. The data in that case is totally, permanently lost. Data on unaffected parts of the platters may be recoverable, but usually data are spread around the platters, so a head crash is really bad news
The read/write head floats just above the platter surface. A piece of dust or even a fingerprint can cause a head crash

Signs of hard disk failure 

Always, hard drives fail with no warning at all. A minute the computer is working well, the next time within a minute you have a "blue screen of death" and all your data get lost at a time.

So, what's the we do learn here?

Often ensure yourself to not rely on warning signs to predict hard drive failure. All the time get involved that your hard disk is going to fail, and back up critical files. Different mechanical components can fail gradually, however, so occasionally you'll know when a drive failure is coming up.

And this warning will come as either: 

Sounds.or
Performance problems. 
So when you notice the warning above make sure you critical files are safe otherwise your going to loose it.