Another benefit of hard disk is that it offers random access to data. No matter on which part of the disk a particular file is located, the read / write head can instantly retrieve it ?at random? so that the operating system can process if further. This combination of very high capacities and random data access is what makes hard drives unique and an ideal media to act as primary data storage inside computers and laptops.



However, it is a sad fact of life that hard disks are not infallible. They crash. When this happens, all the data that you have on your computer becomes inaccessible instantly, leaving you in a state of utter panic. But why do hard disks go bad in the first place?

A hard disk is essentially an electro-mechanical-magnetic device. There is a vertical row of platters inside a hard disk, each of which has a magnetic coating on its surface. All data gets stored on this in the form of magnetic imprints. A read / write head hovers above, reading the data and transferring it to the operating system. A spindle motor spins the platters at a very high number of revolutions per minute.

The current industry standard is 5,400 or 7,200 RPM (revolutions per minute), though disks with an RPM of 15,000 are also beginning to be introduced in the market. In a 7,200 RPM drive, the platters are spinning 120 times a second! The higher the RPM, the faster the computer can boot up, load software and access data. Obviously, with such precise and fast mechanics, there is much that can go wrong with a hard disk.

The spindle motor can burn out, the read / write head can become unhinged and come crashing down on platter surface, scratching it and destroying data stored there. The disk circuits may get fried due to a malfunction or power spike. Then there may be software errors such as a user accidentally deleting a file, reformatting the hard disk or even a virus attack.

It is therefore a good idea to keep your data backed up in a different storage media. This has many benefits. If something goes wrong, you can just take the backup media and reinstall your files onto your hard disk. This will save you time as well as a huge amount of money that may have to be paid to the professional data recovery companies. There are a range of storage media products available in the market to suit all needs and budgets.

Floppy Drives

These have very limited data storage, not exceeding 1.4 MB. Floppies were all the rage about 10 years ago. However, by today's standards, they are quite an old technology and are almost out of fashion now. They can be used for storing text files and not much else as a file containing pictures would easily be much more than the holding capacity of a floppy disk. These disks are also quite unreliable and frequently the computer refuses to recognise them.

Compact Disks (CDs)

Compact disks were responsible for the demise of the floppy disk industry. These can hold up to 700 MB of data or up to 80 minutes of audio. This makes them ideal for the backup needs of most individual users. They are today the industry-standard for removable storage media. These come in rewritable version too and the data can be written and rewritten over them hundreds of times.

Digital Video Disks (DVDs)

DVDs are the latest development of optical disk technology. They can hold up to 8.4 GB of data, much more than a CD. DVDs are currently quite expensive when compared to a CD, but with time their costs are going to come down. It looks like DVDs are gradually going to replace CDs totally in the next four or five years.

Flash Drives

These use a small Flash memory-based card to hold data and are commonly available in capacities of up to 8 GB. Flash drives connect to a computer through the high-speed USB port and are no larger than your thumb, which makes them quite portable. You can easily carry three or four of them in your shirt pocket.

Portable Hard Disks

These offer the same functionality as the regular computer hard disks, but they are portable and can be carried around by the user. Portable disks are used to take a backup of the entire computer hard drive. Most of these come with a software that automatically takes backup at regular intervals, thus leaving the user to concentrate on other tasks.