Inside Hard Drive

Hard drive is the most important component of a computer or a laptop. It is the storage unit that stores massive amount of data in it. Data stored on a hard drive can be accessed randomly and at a high speed.

Hard disk drives were originally developed for Mainframes and mini computers in the year 1956. The first IBM drives was approximately the size of the two refrigerators and could store 5 million 6 bit characters. The current laptop hard drive is about 2.5” and the size of a desktop hard drive is around 3.5” that is 100,000 times smaller with million times increased capacity.

Inside the hard disk drive following components are found:

Platter: The Platter is the flat aluminum disk which holds all the recorded data. A hard drive can have two or more platters stacked up depending on its storage capacity. To increase the durability, the platters are now a days coated with a magnetically retentive substance like oxide or thin-film.

Spindle and Spindle Motor: A spindle is the rotating shaft that holds the platters. The spindle rotates the platter in speed measured in RPM (revolution per minute), usually at the rate of 3,600 to 7,200 RPM.
Spindle Motors are attached directly in the hard drive. Spindle Motor must be noise free and vibrations free for performing read / write operation smoothly.

Actuator Arm: Actuator Arm or Access Arm has the read / write head at the end of the arm. These heads move above the platter and access the data stored in it. The arm doesn’t touch the platter. Two magnets, one above and one below the actuator are located.

Ribbon Cable: With Ribbon Cable the read / write head are attached to the controller board.

Inside a Hard Drive

Cables and Connectors

The most important connector is Interface Connector, whichis carrier of data and command to and from the hard disk. Other cables found are Power Connector and optional Ground Connector.

All the internal components of a hard disk is enclosed in a rectangular Drive Casing.

Terms Related

Area Density: The amount of data that square inch of the platter can hold is measured in area density. The highest record of the area density is 16.1GB (gigabits) per square inch, by Seagate

Related Information

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Is your drive is not booting? Are you suffering data loss due to hard drive failure? Do you wish to get back all the lost / missing data from the drive? Remo Recover software can successfully retrieve all the contents of the failed hard drive.

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Do you want to sell your used hard drive after formatting its contents. Do you know it is possible to recover data even after formatting? To learn how to erase data beyond recovery, follow the article.