Data loss can occur due to many reasons. These can be broadly divided into two parts – physical and logical errors.
The former relate to any kind of hardware damage or malfunction, while the latter are caused by damage to the software such as missing or corrupted code, accidental deletion of data files by the user or reformatting of the data storage media. There are many digital storage devices available in the market, from hard disks on one end to tiny floppy disks on the other. Each of these is susceptible to data loss.
Hard Disks
The most serious but quite common data-loss situation for a hard drive occurs when it “crashes.” In this, the read / write head makes physical contact with the rapidly spinning platters and damages the data-recording surface. It is very difficult to recover data from such cases, even for a professional recovery company.
Another major cause of hard drive malfunction is when the ball bearings of spindle motor give way due to normal wear and tear. The controller card and the circuit board may also get fried in an electric surge. Impact trauma where the disk hits the ground with a thud is also responsible for damaging components. To carry out repairs to a hard disk, it is essential to have a clean room with dust-free air where the innards of the drive can be safely exposed.
Optical Drives
Optical drives are made of very tough plastic. But an exposed data-recording surface is their Achilles’ heel. In the disks, the main reason for data loss is a corrupted surface which does not allow the laser beam to read the pit pattern properly. This occurs due to scratches, contaminants such as dust or some thick, viscous liquid spilling over it. If you have to save an optical disk from data loss, it is essential to keep it safely enclosed in the drive tray or, while not in use, in a protective plastic case.
The disk is made of plastic which can bear a large amount of pressure. However, it is sensitive to heat and should not be kept near a fire or in direct sunlight, such as on the dashboard of a car. The disk should also be protected from being placed under heavier objects as it may snap into pieces.
USB Drives
These are very compact devices that can easily be dangled from a keychain (hence also called keychain drives). Unlike hard disks, they have no moving parts or even a magnetic data recording surface inside. Instead, they record data on a flash memory card that hardly uses any power.
USB drives are very reliable devices because they are a very simple storage media built around a single card that is enclosed in a tough plastic case. They hardly get spoilt unless you manage to step on them or crush them under something. The drives can also lose data if they get immersed in water or dropped in a fire.
Tape Drives
Tape drives store data the old fashioned way over magnetic tapes which are enclosed in a plastic cartridge. These have one of the lowest costs per MB of data stored among all digital media. They are meant for long-term archival data storage. The most common way they lose data is due to over-use.
The tape in a drive runs brushing past the read / write head and over time, it gets eroded. This is when it is in the danger of losing data. The tape may break or get jammed in the drive and thus have to be cut and pasted for it to run again. The tape cartridges also have to be stored in a cool and dry place to ensure that the tape does not weaken or attract a fungal outgrowth over time.
How to Prevent Data Loss?
Data loss is a very common but nevertheless scary situation. There is hardly any user of digital devices in the world who has not suffered data loss one time or another. What is the solution? There is none. Data storage media is made up of components that have a fixed life.
They are sooner or later going to give way, though you can extend their life and ensure that they do not suffer a mid-life crisis by taking good care of your digital media devices. In the world of information technology, backup is always better than cure.
