Every piece of information was put down on paper and meticulously filed. As a result, all offices had ceiling-high filing cabinets and shelves choking with paper files. The files gradually became dog-eared and fragile with use. Important documents had to be microfilmed and stored in special libraries with ideal temperature and humidity. It seemed that modern economy could just go so far with paper files and no further.

That is why when computers got invented, they seemed God's gift to mankind. They were like manna from heaven for offices getting swamped with paper files. In the modern age driven by information technology, most information now exists digitally as a string of ones and zeros. At the heart of a computer is a silicon processor. It is nothing but a tiny chip that has millions of microscopic transistors residing on it. These transistors can exist either in an ?off? state (zero) or an ?on? state (one).

Together, they make processing of digital data possible. The power of the processor is properly utilized by an operating system that runs a variety of software according to the wishes of the computer user. The processor can only comprehend information in a digital form, that is, as a string of ones and zeroes. This digital data is volatile and unstable. It can get lost due to a variety of reasons, which are mainly divided into hardware and software errors.

In hardware errors, as the name suggests, some part of the data-storage device ? usually the hard drive ? malfunctions and the data cannot be accessed. This can be due to some problem with the spindle motor, platters, read-and-write head, controller card, power supply, circuit board and so on. In an optical disk, the data-recording surface may become corrupted or damaged. A USB Flash drive may get crushed underfoot or fall in water or fire.

Software errors relate to corruption of the data structure and virus attack. One of the most common software errors occurs when a data file is accidentally deleted by the user and the Recycle Bin emptied. This can happen due to many reasons. Usually, you delete a data file from the computer thinking it is no longer needed. Later on, you realise that it actually had some information that is now required. Sometimes, a data file may have a misleading title, leading you to purge it from your computer. Afterwards, you are left wringing you hands as you get to know that the file was actually not what you thought it was.

A more severe form of user error happens when the entire hard disk is mistakenly reformatted. This wipes off all data from the disk and you can no longer access what was stored on it. Apart from hard disks, other storage media can be reformatted too, such as CDs, DVDs, Flash drives, memory cards, floppy disks and portable hard disks, leading to total data loss. The surprising thing in all these cases is that your lost file can actually be easily recovered. But how is this possible? For this, you have to understand how the Windows operating system manages your files.

Windows keeps a list of all your data files existing on a storage media in a file allocation table (FAT). This table tells the operating system which file is stored on which part of the data-recording surface. When you actually delete a file, the data is not erased. Only the name of the file is erased from FAT and Windows earmarks that space as vacant and available for storing any other data.

The same thing happens when a hard disk or any other storage media such as a CD or Flash memory card is reformatted. Only the FAT is wiped clean, but the data files still remain, waiting to be overwritten by fresh data. The data files thus become invisible to Windows but they are still very much there on the data-storage media.

Any Do-It-Yourself worth its salt can easily recover such files by bypassing the operating system and directly showing you the files that still exist on the storage device. You can simply click on the file names and recover them quickly. The only precaution you have to take is that you should cease working on the storage device immediately. This is to prevent the risk of the data files being overwritten by the operating system with a fresh set of data. If this happens, then your old files will be permanently lost.