| Hard Disk: An Introduction Hard disk is a non-volatile | | | | entire surface of the platter. Contemporary hard |
| data storage device that stores electronic data on a | | | | drives use a voice coil actuator, which controls the |
| magnetic surface layered onto hard disk platters. | | | | movement of a coil toward or away from a |
| Word Hard is use to differentiate it from a soft, or | | | | permanent magnet based on the amount of current |
| floppy disk. Hard disks hold more data and can store | | | | flowing through it.Fundamental structures of all hard |
| from 10 to more than 100 gigabytes, whereas most | | | | disk are same, and are composed of the same |
| floppies have a maximum storage capacity of 1.4 | | | | physical features, but their performance depends on |
| megabytes and in addition are faster too. Normally | | | | the quality of their inner components.Hard Disk Failure: |
| term hard disk is much familiar with computers only | | | | Hard Disk Failure occurs when a hard disk drive |
| but it is widely used as network attached storage for | | | | malfunctions and the accumulate data cannot be |
| large volume storage. Furthermore, appliance of hard | | | | accessed. It may happen in the course of normal |
| disk drives spread out to video recorders, audio | | | | operation due to an internal or external factor. Disk |
| players, digital organizers, digital cameras, and even in | | | | failure varies and the most common is "Head Crash" |
| latest cellular telephones.Reynold Johnson invented | | | | where the internal read and write head of a device |
| the first hard disk in 1955 for IBM 305 computer with | | | | touches a platter or magnetic storage surface often |
| fifty 24 inch platters and total capacity of five million | | | | grinding away the magnetic surface. Head hover just |
| characters, and in 1956 - first commercial hard disk | | | | micrometers from the platters plane which makes |
| was launched with 5 megabyte capacity, the IBM 350 | | | | such collision a common one. This sort of crash |
| RAMAC disk drive. Within time frame of 50 years | | | | usually invites severe data loss and unprofessional |
| and rapid progress in technical enhancement, we | | | | data recovery attempts results further damage to |
| have now reached to latest 2006 - First 750 GB hard | | | | the remaining data. Hard drive also includes other |
| drive from (Seagate) and First 200 GB 2.5" Hard | | | | controller electronics i.e., semiconductors, valves or |
| Drive utilizing Perpendicular recording (Toshiba).Heart | | | | electronic circuits, and major components such as |
| of hard disk consists of four basic components: The | | | | Platters, Spindle Motor and Head Actuator. Failure of |
| Platters: Platters are the actual disks inside the drive | | | | any these devices may cause a hard disk |
| that store the magnetized data. Conventional platters | | | | failure.Factors causes disk failure are numerous, yet |
| are made of a light aluminum alloy and coated with | | | | most common are power surges, voltage |
| magnetize-able material but latest technology uses | | | | fluctuations, electronic malfunction, physical shock, |
| glass or ceramic platters as they are thinner and also | | | | wear and tear, corrosion, exposure to high magnetic |
| heat resisting. Most drives have at least two platters | | | | waves, sharp impact, high temperature exposure |
| and the larger the storage capacity of the drive, the | | | | etc.The phenomena of hard disk failure is raising |
| more platters there are.The Spindle Motor: Hard disk | | | | higher and higher; as to increase the read and write |
| drive consists of a spindle on which the platters spin | | | | speed, today we have latest hard disk rotating |
| at a constant RPM. Moving along and between the | | | | amazingly faster and this immense revolving speed |
| platters on a common arm are read-write heads. The | | | | generates massive centrifugal force, a single adverse |
| platters in a drive are divided by disk spacers and are | | | | cause in the course of normal operation can cause |
| clamped to a revolving spindle that turns all the | | | | severe hard disk failure.Hard Disk Data Recovery: |
| platters in a uniform motion. The spindle motor is built | | | | Hard disk data recovery is the process of recovering |
| right into the spindle and rotates the platters at a | | | | the trapped data from the damage hard disk device, |
| constant set rate ranging from 3,600 to 7,200 | | | | when it can not be accessed in normal circumstance. |
| RPM.The Read/Write Heads: Read/write heads read | | | | Several Techniques are used to retrieving data from |
| and write data to the platters, and each head is fixed | | | | damaged hard disk and techniques vary accordingly. |
| to a single actuator shaft so that all the heads move | | | | It can be done by moving disk drive to a working |
| in harmony. Typically, only one of the heads is active | | | | CPU, or may have to open the disk drive and replace |
| at a time either reading or writing data. When not in | | | | parts such as read/write heads, arms and chips and |
| use, the heads are inactive, but when in motion the | | | | sometime the platters have to be removed and |
| spinning of the platters generate air pressure that | | | | placed into another drive. Physical damage can not be |
| lifts the heads off the platters. The space between | | | | repaired by the general users, as it requires clean and |
| the platter and the head is so minute that even one | | | | dust free lab environment, in addition proper |
| dust particle or a fingerprint could disable the spin. | | | | hardware and technical expertise; where under |
| When the platters cease spinning the heads come to | | | | microscopic examination with proper tool and |
| rest, at a preset position on the heads, called the | | | | techniques, the damage drive is put on to |
| landing zone.The Head Actuator: All the heads are | | | | observation for data salvaging.In case of worse |
| attached to a single head actuator arm, which moves | | | | happening, do consult Digital Image Recovery Service |
| the heads around the platters. The Actuator arm | | | | for saving your important data trapped within the |
| moves the heads on an arc across the platters as | | | | damage device. |
| they spin, allowing each head to access almost the | | | | |