Data loss is something that is as old as digital computers. In fact, an entire industry has arisen in the last couple of decades that specialises in extracting data from damaged storage devices.

There are many types of digital media – both removable and non-removable – available today for storing data, right from optical disks with a 740 MB capacity to portable hard disks that can hold up to 500 GB of data. Other devices include floppy drives, tape drives and USB drives. There is thus a storage media to suit everyone’s budget and requirement.

All storage media essentially have a data recording surface on which information is written in a variety of ways. The optical disks store data on a plastic surface by using a laser to etch a pattern of microscopic pits, whose absence and presence represent one and zero, respectively. This pattern is read by a laser beam that bounces off the disk surface back to the optical drive lens.

Hard disks, floppy disks and tape drives use the tried-and-tested technology of magnetic storage. The recording surface carries a thin coat of magnetic paint. Over this, data is written by a read / write head by rearranging the polarity of the magnetic particles. USB drives on the other hand use a tiny flash memory chip to store data whose microscopic transistors are flipped on or off by electric current.

Regardless of how the data is stored, digital information can get lost from any storage media without any warning. Loss of critical data is the stuff nightmares of computer users are made of. Such a loss can result in massive financial setback, disruption of business activity, loss of intellectual property collected over the years and bad reputation in the market place for a company. Indeed, according to one estimate, two out of every five businesses that experience total data loss are unable to survive and go belly up after some months. In cases of data loss, prevention is the best cure.

There are a vast range of digital storage media available in the market that allows one to take regular data backups. However, the most fool-proof data backup arrangement is offered by remote backup companies. In this, a copy of the data leaves your premises at an appointed hour every day to reside on the dedicated servers provided by the service provider. Anytime there is a loss of data, you download your data from the servers and are back on your feet in no time.

All incidents of data loss can be attributed to three main causes.

Software Errors

Software errors, also called logical errors, occur due to a problem with the digital data itself. The most common cause of data loss due to these errors is when a user deletes a file accidentally and empties the recycle bin. Many a time, the entire storage media is reformatted, thus wiping all data off it, before the realisation dawns that some important files were residing there. Virus attacks are very common these days, especially through the Internet. Other software causes include corruption of file structure and system files.

Hardware Errors

Hardware errors relate to the physical characteristics and components of the storage media. These include scratches, contaminants and other types of corruption of data recording surface. In a hard disk, the head may crash, the spindle motor may stop whirring and the controller card may get fried. An optical disk may break, melt or get damaged otherwise. It may also get bent once exposed to strong heat or direct sunlight.

Hardware errors include cases of water and fire damage as well as impact trauma such as when a hard disk is dropped to the ground and stops working. A USB drive may get crushed under a heavy object or fall into fire or water. The magnetic tape of a tape drive may break or get snagged in the rollers of the read / write head. All these hardware errors would result in data loss.

Disasters

Disasters do not occur frequently, but once they do, they inflict massive damage to the data storage devices. These can be either natural or man-made. The former includes all cases of fury of Mother Nature, such as volcano eruption, incessant rainfall that results in a river breaking banks and flooding the entire neighbourhood, mud slides, earthquakes, lightning strike, cyclones, storms and building collapse.

Not all disasters are natural, however. Some are man-made, as illustrated so poignantly by the 9/11 World Trade Center tragedy. These include cases of sabotage by disgruntled employees, arson and bomb explosions. When such a disaster comes visiting a premises, all digital devices and storage media – original as well as backup – located inside get totally destroyed. Data recovery in such cases is a very expensive affair.