Computers and laptops generate a lot of data in their routine, day-to-day operations, whether at office or home. This data is crucial for the user because if it is lost for any reason, no further work is possible and everything comes to a standstill. With data loss, individuals can no longer access their precious photos, emails, videos and text files. For companies, it translates into huge financial losses which may even threaten their very existence.

The data that computers and other digital devices generate has to be stored at a safe and secure place so that it can be reused. A variety of storage devices exist in the market that range from optical disks such as compact discs (CDs) and digital video discs (DVDs) to hard disks, floppy drives, tape drives and USB Flash drives. These use a variety of methods to hold data, such as a surface pattern, magnetic imprints or an electric charge.

Modern computers have mind-bogglingly fast processing speeds and need a storage device that can keep pace with the efficiency of their operations. The ideal primary storage media for them is one which is able to store a huge amount of data, is reliable and, most important of all, can retrieve any data immediately regardless of on which part of the recording surface it has been stored.

There is only one storage device that currently fits this bill ? a hard disk. It is truly an amazing piece of machinery and engineering excellence. The disk stores data on the surface of a series of metal platters which carry a thin coat of magnetic paint. These are arranged in a vertical series and rest on a single spindle motor. The motor is capable of spinning the platters at a fixed number of revolutions per minute (RPM).

This figure for commonly available hard disks is either 5,400 RPMs or 7,200 RPMs. The faster the motor is able to spin the platters, the less time the computer has to spend to seek the data. The data on the platters is accessed and modified by a read-and-write head that hovers a sub-micron level above their metallic surface. The circuit board supplies power to the disk while the controller card acts as its interface with the operating system. The entire hard disk assembly is housed inside a strong metal case which is screwed securely to the CPU and connected to the motherboard with a data cable.

Data residing on the hard disk is quite unstable as it is nothing more than magnetic patterns that are interpreted in a meaningful way by the processor. The pattern can be destroyed or corrupted due to a variety of causes, which mainly relate to hardware or software errors. The former entails data loss due to malfunction of any physical component of the disk such as the read-and-write head becoming unhinged and crashing on the platter surface, thus scratching it and damaging the recorded data.

Software (logical) errors relate to corruption or disappearance of data due to a variety of factors such as virus attack or accidental deletion of files by the user. One of the most serious software errors occurs when the user accidentally deletes a partition in the hard drive. The moment this happens, all data existing within the partition is immediately lost and cannot be accessed by the operating system.

The only option in these cases is to run a partition editor such as GetDataBack for the file allocation table. This can restore the partition but there is no guarantee that the data existing inside the partition can be recovered. If the data still remains lost, what is actually needed is to carry out repairs to the file system so that the missing files again become visible to the operating system and the user can access them.

Carrying out file system repair is way beyond the capabilities of the shrink-wrapped data-recovery software available in the market. Also, there is a danger of overwriting the invisible data. If this happens and the operating system stores new files over the already existing data, then the lost data is lost permanently.

This is where professional data recovery companies come in. They have the required expertise and infrastructure to carry out a detailed review of the logical structure of your hard disks and carry out the required repairs to the system files so that the data can be safely extracted. It is a laborious and time-consuming work but is well worth it if you absolutely must get your missing data files back.